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  <h1>Source code for pyspark.accumulators</h1><div class="highlight"><pre>
<span class="c">#</span>
<span class="c"># Licensed to the Apache Software Foundation (ASF) under one or more</span>
<span class="c"># contributor license agreements.  See the NOTICE file distributed with</span>
<span class="c"># this work for additional information regarding copyright ownership.</span>
<span class="c"># The ASF licenses this file to You under the Apache License, Version 2.0</span>
<span class="c"># (the &quot;License&quot;); you may not use this file except in compliance with</span>
<span class="c"># the License.  You may obtain a copy of the License at</span>
<span class="c">#</span>
<span class="c">#    http://www.apache.org/licenses/LICENSE-2.0</span>
<span class="c">#</span>
<span class="c"># Unless required by applicable law or agreed to in writing, software</span>
<span class="c"># distributed under the License is distributed on an &quot;AS IS&quot; BASIS,</span>
<span class="c"># WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span>
<span class="c"># See the License for the specific language governing permissions and</span>
<span class="c"># limitations under the License.</span>
<span class="c">#</span>

<span class="sd">&quot;&quot;&quot;</span>
<span class="sd">&gt;&gt;&gt; from pyspark.context import SparkContext</span>
<span class="sd">&gt;&gt;&gt; sc = SparkContext(&#39;local&#39;, &#39;test&#39;)</span>
<span class="sd">&gt;&gt;&gt; a = sc.accumulator(1)</span>
<span class="sd">&gt;&gt;&gt; a.value</span>
<span class="sd">1</span>
<span class="sd">&gt;&gt;&gt; a.value = 2</span>
<span class="sd">&gt;&gt;&gt; a.value</span>
<span class="sd">2</span>
<span class="sd">&gt;&gt;&gt; a += 5</span>
<span class="sd">&gt;&gt;&gt; a.value</span>
<span class="sd">7</span>

<span class="sd">&gt;&gt;&gt; sc.accumulator(1.0).value</span>
<span class="sd">1.0</span>

<span class="sd">&gt;&gt;&gt; sc.accumulator(1j).value</span>
<span class="sd">1j</span>

<span class="sd">&gt;&gt;&gt; rdd = sc.parallelize([1,2,3])</span>
<span class="sd">&gt;&gt;&gt; def f(x):</span>
<span class="sd">...     global a</span>
<span class="sd">...     a += x</span>
<span class="sd">&gt;&gt;&gt; rdd.foreach(f)</span>
<span class="sd">&gt;&gt;&gt; a.value</span>
<span class="sd">13</span>

<span class="sd">&gt;&gt;&gt; b = sc.accumulator(0)</span>
<span class="sd">&gt;&gt;&gt; def g(x):</span>
<span class="sd">...     b.add(x)</span>
<span class="sd">&gt;&gt;&gt; rdd.foreach(g)</span>
<span class="sd">&gt;&gt;&gt; b.value</span>
<span class="sd">6</span>

<span class="sd">&gt;&gt;&gt; from pyspark.accumulators import AccumulatorParam</span>
<span class="sd">&gt;&gt;&gt; class VectorAccumulatorParam(AccumulatorParam):</span>
<span class="sd">...     def zero(self, value):</span>
<span class="sd">...         return [0.0] * len(value)</span>
<span class="sd">...     def addInPlace(self, val1, val2):</span>
<span class="sd">...         for i in range(len(val1)):</span>
<span class="sd">...              val1[i] += val2[i]</span>
<span class="sd">...         return val1</span>
<span class="sd">&gt;&gt;&gt; va = sc.accumulator([1.0, 2.0, 3.0], VectorAccumulatorParam())</span>
<span class="sd">&gt;&gt;&gt; va.value</span>
<span class="sd">[1.0, 2.0, 3.0]</span>
<span class="sd">&gt;&gt;&gt; def g(x):</span>
<span class="sd">...     global va</span>
<span class="sd">...     va += [x] * 3</span>
<span class="sd">&gt;&gt;&gt; rdd.foreach(g)</span>
<span class="sd">&gt;&gt;&gt; va.value</span>
<span class="sd">[7.0, 8.0, 9.0]</span>

<span class="sd">&gt;&gt;&gt; rdd.map(lambda x: a.value).collect() # doctest: +IGNORE_EXCEPTION_DETAIL</span>
<span class="sd">Traceback (most recent call last):</span>
<span class="sd">    ...</span>
<span class="sd">Py4JJavaError:...</span>

<span class="sd">&gt;&gt;&gt; def h(x):</span>
<span class="sd">...     global a</span>
<span class="sd">...     a.value = 7</span>
<span class="sd">&gt;&gt;&gt; rdd.foreach(h) # doctest: +IGNORE_EXCEPTION_DETAIL</span>
<span class="sd">Traceback (most recent call last):</span>
<span class="sd">    ...</span>
<span class="sd">Py4JJavaError:...</span>

<span class="sd">&gt;&gt;&gt; sc.accumulator([1.0, 2.0, 3.0]) # doctest: +IGNORE_EXCEPTION_DETAIL</span>
<span class="sd">Traceback (most recent call last):</span>
<span class="sd">    ...</span>
<span class="sd">TypeError:...</span>
<span class="sd">&quot;&quot;&quot;</span>

<span class="kn">import</span> <span class="nn">sys</span>
<span class="kn">import</span> <span class="nn">select</span>
<span class="kn">import</span> <span class="nn">struct</span>
<span class="k">if</span> <span class="n">sys</span><span class="o">.</span><span class="n">version</span> <span class="o">&lt;</span> <span class="s">&#39;3&#39;</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">SocketServer</span>
<span class="k">else</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">socketserver</span> <span class="kn">as</span> <span class="nn">SocketServer</span>
<span class="kn">import</span> <span class="nn">threading</span>
<span class="kn">from</span> <span class="nn">pyspark.cloudpickle</span> <span class="kn">import</span> <span class="n">CloudPickler</span>
<span class="kn">from</span> <span class="nn">pyspark.serializers</span> <span class="kn">import</span> <span class="n">read_int</span><span class="p">,</span> <span class="n">PickleSerializer</span>


<span class="n">__all__</span> <span class="o">=</span> <span class="p">[</span><span class="s">&#39;Accumulator&#39;</span><span class="p">,</span> <span class="s">&#39;AccumulatorParam&#39;</span><span class="p">]</span>


<span class="n">pickleSer</span> <span class="o">=</span> <span class="n">PickleSerializer</span><span class="p">()</span>

<span class="c"># Holds accumulators registered on the current machine, keyed by ID. This is then used to send</span>
<span class="c"># the local accumulator updates back to the driver program at the end of a task.</span>
<span class="n">_accumulatorRegistry</span> <span class="o">=</span> <span class="p">{}</span>


<span class="k">def</span> <span class="nf">_deserialize_accumulator</span><span class="p">(</span><span class="n">aid</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">):</span>
    <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span>
    <span class="n">accum</span> <span class="o">=</span> <span class="n">Accumulator</span><span class="p">(</span><span class="n">aid</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">)</span>
    <span class="n">accum</span><span class="o">.</span><span class="n">_deserialized</span> <span class="o">=</span> <span class="bp">True</span>
    <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">=</span> <span class="n">accum</span>
    <span class="k">return</span> <span class="n">accum</span>


<div class="viewcode-block" id="Accumulator"><a class="viewcode-back" href="../../pyspark.html#pyspark.Accumulator">[docs]</a><span class="k">class</span> <span class="nc">Accumulator</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    A shared variable that can be accumulated, i.e., has a commutative and associative &quot;add&quot;</span>
<span class="sd">    operation. Worker tasks on a Spark cluster can add values to an Accumulator with the C{+=}</span>
<span class="sd">    operator, but only the driver program is allowed to access its value, using C{value}.</span>
<span class="sd">    Updates from the workers get propagated automatically to the driver program.</span>

<span class="sd">    While C{SparkContext} supports accumulators for primitive data types like C{int} and</span>
<span class="sd">    C{float}, users can also define accumulators for custom types by providing a custom</span>
<span class="sd">    L{AccumulatorParam} object. Refer to the doctest of this module for an example.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">aid</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;Create a new Accumulator with a given initial value and AccumulatorParam object&quot;&quot;&quot;</span>
        <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">aid</span> <span class="o">=</span> <span class="n">aid</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span> <span class="o">=</span> <span class="n">accum_param</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="n">value</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span> <span class="o">=</span> <span class="bp">False</span>
        <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span>

    <span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;Custom serialization; saves the zero value from our AccumulatorParam&quot;&quot;&quot;</span>
        <span class="n">param</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span>
        <span class="k">return</span> <span class="p">(</span><span class="n">_deserialize_accumulator</span><span class="p">,</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">aid</span><span class="p">,</span> <span class="n">param</span><span class="o">.</span><span class="n">zero</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">),</span> <span class="n">param</span><span class="p">))</span>

    <span class="nd">@property</span>
    <span class="k">def</span> <span class="nf">value</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;Get the accumulator&#39;s value; only usable in driver program&quot;&quot;&quot;</span>
        <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">Exception</span><span class="p">(</span><span class="s">&quot;Accumulator.value cannot be accessed inside tasks&quot;</span><span class="p">)</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_value</span>

    <span class="nd">@value.setter</span>
    <span class="k">def</span> <span class="nf">value</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;Sets the accumulator&#39;s value; only usable in driver program&quot;&quot;&quot;</span>
        <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">Exception</span><span class="p">(</span><span class="s">&quot;Accumulator.value cannot be accessed inside tasks&quot;</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="n">value</span>

<div class="viewcode-block" id="Accumulator.add"><a class="viewcode-back" href="../../pyspark.html#pyspark.Accumulator.add">[docs]</a>    <span class="k">def</span> <span class="nf">add</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">term</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;Adds a term to this accumulator&#39;s value&quot;&quot;&quot;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span><span class="o">.</span><span class="n">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">,</span> <span class="n">term</span><span class="p">)</span>
</div>
    <span class="k">def</span> <span class="nf">__iadd__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">term</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;The += operator; adds a term to this accumulator&#39;s value&quot;&quot;&quot;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">term</span><span class="p">)</span>
        <span class="k">return</span> <span class="bp">self</span>

    <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;Accumulator&lt;id=</span><span class="si">%i</span><span class="s">, value=</span><span class="si">%s</span><span class="s">&gt;&quot;</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">aid</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">)</span>

</div>
<div class="viewcode-block" id="AccumulatorParam"><a class="viewcode-back" href="../../pyspark.html#pyspark.AccumulatorParam">[docs]</a><span class="k">class</span> <span class="nc">AccumulatorParam</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Helper object that defines how to accumulate values of a given type.</span>
<span class="sd">    &quot;&quot;&quot;</span>

<div class="viewcode-block" id="AccumulatorParam.zero"><a class="viewcode-back" href="../../pyspark.html#pyspark.AccumulatorParam.zero">[docs]</a>    <span class="k">def</span> <span class="nf">zero</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Provide a &quot;zero value&quot; for the type, compatible in dimensions with the</span>
<span class="sd">        provided C{value} (e.g., a zero vector)</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>
</div>
<div class="viewcode-block" id="AccumulatorParam.addInPlace"><a class="viewcode-back" href="../../pyspark.html#pyspark.AccumulatorParam.addInPlace">[docs]</a>    <span class="k">def</span> <span class="nf">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value1</span><span class="p">,</span> <span class="n">value2</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Add two values of the accumulator&#39;s data type, returning a new value;</span>
<span class="sd">        for efficiency, can also update C{value1} in place and return it.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>

</div></div>
<span class="k">class</span> <span class="nc">AddingAccumulatorParam</span><span class="p">(</span><span class="n">AccumulatorParam</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    An AccumulatorParam that uses the + operators to add values. Designed for simple types</span>
<span class="sd">    such as integers, floats, and lists. Requires the zero value for the underlying type</span>
<span class="sd">    as a parameter.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">zero_value</span> <span class="o">=</span> <span class="n">zero_value</span>

    <span class="k">def</span> <span class="nf">zero</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">zero_value</span>

    <span class="k">def</span> <span class="nf">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value1</span><span class="p">,</span> <span class="n">value2</span><span class="p">):</span>
        <span class="n">value1</span> <span class="o">+=</span> <span class="n">value2</span>
        <span class="k">return</span> <span class="n">value1</span>


<span class="c"># Singleton accumulator params for some standard types</span>
<span class="n">INT_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
<span class="n">FLOAT_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mf">0.0</span><span class="p">)</span>
<span class="n">COMPLEX_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mf">0.0j</span><span class="p">)</span>


<span class="k">class</span> <span class="nc">_UpdateRequestHandler</span><span class="p">(</span><span class="n">SocketServer</span><span class="o">.</span><span class="n">StreamRequestHandler</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    This handler will keep polling updates from the same socket until the</span>
<span class="sd">    server is shutdown.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">handle</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span>
        <span class="k">while</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">server</span><span class="o">.</span><span class="n">server_shutdown</span><span class="p">:</span>
            <span class="c"># Poll every 1 second for new data -- don&#39;t block in case of shutdown.</span>
            <span class="n">r</span><span class="p">,</span> <span class="n">_</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">select</span><span class="o">.</span><span class="n">select</span><span class="p">([</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">],</span> <span class="p">[],</span> <span class="p">[],</span> <span class="mi">1</span><span class="p">)</span>
            <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">rfile</span> <span class="ow">in</span> <span class="n">r</span><span class="p">:</span>
                <span class="n">num_updates</span> <span class="o">=</span> <span class="n">read_int</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">)</span>
                <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">num_updates</span><span class="p">):</span>
                    <span class="p">(</span><span class="n">aid</span><span class="p">,</span> <span class="n">update</span><span class="p">)</span> <span class="o">=</span> <span class="n">pickleSer</span><span class="o">.</span><span class="n">_read_with_length</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">)</span>
                    <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">+=</span> <span class="n">update</span>
                <span class="c"># Write a byte in acknowledgement</span>
                <span class="bp">self</span><span class="o">.</span><span class="n">wfile</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">struct</span><span class="o">.</span><span class="n">pack</span><span class="p">(</span><span class="s">&quot;!b&quot;</span><span class="p">,</span> <span class="mi">1</span><span class="p">))</span>


<span class="k">class</span> <span class="nc">AccumulatorServer</span><span class="p">(</span><span class="n">SocketServer</span><span class="o">.</span><span class="n">TCPServer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    A simple TCP server that intercepts shutdown() in order to interrupt</span>
<span class="sd">    our continuous polling on the handler.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="n">server_shutdown</span> <span class="o">=</span> <span class="bp">False</span>

    <span class="k">def</span> <span class="nf">shutdown</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">server_shutdown</span> <span class="o">=</span> <span class="bp">True</span>
        <span class="n">SocketServer</span><span class="o">.</span><span class="n">TCPServer</span><span class="o">.</span><span class="n">shutdown</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">server_close</span><span class="p">()</span>


<span class="k">def</span> <span class="nf">_start_update_server</span><span class="p">():</span>
    <span class="sd">&quot;&quot;&quot;Start a TCP server to receive accumulator updates in a daemon thread, and returns it&quot;&quot;&quot;</span>
    <span class="n">server</span> <span class="o">=</span> <span class="n">AccumulatorServer</span><span class="p">((</span><span class="s">&quot;localhost&quot;</span><span class="p">,</span> <span class="mi">0</span><span class="p">),</span> <span class="n">_UpdateRequestHandler</span><span class="p">)</span>
    <span class="n">thread</span> <span class="o">=</span> <span class="n">threading</span><span class="o">.</span><span class="n">Thread</span><span class="p">(</span><span class="n">target</span><span class="o">=</span><span class="n">server</span><span class="o">.</span><span class="n">serve_forever</span><span class="p">)</span>
    <span class="n">thread</span><span class="o">.</span><span class="n">daemon</span> <span class="o">=</span> <span class="bp">True</span>
    <span class="n">thread</span><span class="o">.</span><span class="n">start</span><span class="p">()</span>
    <span class="k">return</span> <span class="n">server</span>

<span class="k">if</span> <span class="n">__name__</span> <span class="o">==</span> <span class="s">&quot;__main__&quot;</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">doctest</span>
    <span class="p">(</span><span class="n">failure_count</span><span class="p">,</span> <span class="n">test_count</span><span class="p">)</span> <span class="o">=</span> <span class="n">doctest</span><span class="o">.</span><span class="n">testmod</span><span class="p">()</span>
    <span class="k">if</span> <span class="n">failure_count</span><span class="p">:</span>
        <span class="nb">exit</span><span class="p">(</span><span class="o">-</span><span class="mi">1</span><span class="p">)</span>
</pre></div>

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