<h3 dir="auto">Actual Behavior</h3>
<p dir="auto">When trying to create new flask object, I get following error:</p>
<div class="highlight highlight-source-python notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="&gt;&gt;&gt; from flask import Flask
&gt;&gt;&gt; flask_app = Flask(__name__)
python: ../Python-2.7.14/Python/symtable.c:1319: symtable_visit_params: Assertion `arg-&gt;v.Name.ctx == Param || (arg-&gt;v.Name.ctx == Store &amp;&amp; !toplevel)' failed.
Aborted
"><pre class="notranslate"><span class="pl-c1">&gt;&gt;</span><span class="pl-c1">&gt;</span> <span class="pl-k">from</span> <span class="pl-s1">flask</span> <span class="pl-k">import</span> <span class="pl-v">Flask</span>
<span class="pl-c1">&gt;&gt;</span><span class="pl-c1">&gt;</span> <span class="pl-s1">flask_app</span> <span class="pl-c1">=</span> <span class="pl-v">Flask</span>(<span class="pl-s1">__name__</span>)
<span class="pl-s1">python</span>: ..<span class="pl-c1">/</span><span class="pl-v">Python</span><span class="pl-c1">-</span><span class="pl-c1">2.7</span>.<span class="pl-c1">14</span><span class="pl-c1">/</span><span class="pl-v">Python</span><span class="pl-c1">/</span><span class="pl-s1">symtable</span>.<span class="pl-s1">c</span>:<span class="pl-c1">1319</span>: <span class="pl-s1">symtable_visit_params</span>: <span class="pl-v">Assertion</span> `<span class="pl-s1">arg</span><span class="pl-c1">-&gt;</span><span class="pl-s1">v</span>.<span class="pl-v">Name</span>.<span class="pl-s1">ctx</span> <span class="pl-c1">==</span> <span class="pl-v">Param</span> <span class="pl-c1">|</span><span class="pl-c1">|</span> (<span class="pl-s1">arg</span><span class="pl-c1">-</span><span class="pl-c1">&gt;</span><span class="pl-s1">v</span>.<span class="pl-v">Name</span>.<span class="pl-s1">ctx</span> <span class="pl-c1">==</span> <span class="pl-v">Store</span> <span class="pl-c1">&amp;</span><span class="pl-c1">&amp;</span> !t<span class="pl-s1">oplevel</span>)' <span class="pl-s1">failed</span>.
<span class="pl-v">Aborted</span></pre></div>
<h3 dir="auto">Environment</h3>
<ul dir="auto">
<li>Python version: 2.7.14</li>
<li>Flask version: 1.0.3</li>
<li>Werkzeug version: 0.15.4</li>
</ul>
<p dir="auto">When trying to create new flask object, I get following error:</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="&gt;&gt;&gt; from flask import Flask
&gt;&gt;&gt; flask_app = Flask(__name__)
python: /mnt/builds/jenkins-builds/workspace/pulsar-8/RC/icedge-apl-4/build-intel-apollolake/tmp/work/core2-64-wrs-linux/python/2.7.9-r1/Python-2.7.9/Python/symtable.c:1319: symtable_visit_params: Assertion `arg-&gt;v.Name.ctx == Param || (arg-&gt;v.Name.ctx == Store &amp;&amp; !toplevel)' failed.
Aborted (core dumped)"><pre class="notranslate"><code class="notranslate">&gt;&gt;&gt; from flask import Flask
&gt;&gt;&gt; flask_app = Flask(__name__)
python: /mnt/builds/jenkins-builds/workspace/pulsar-8/RC/icedge-apl-4/build-intel-apollolake/tmp/work/core2-64-wrs-linux/python/2.7.9-r1/Python-2.7.9/Python/symtable.c:1319: symtable_visit_params: Assertion `arg-&gt;v.Name.ctx == Param || (arg-&gt;v.Name.ctx == Store &amp;&amp; !toplevel)' failed.
Aborted (core dumped)
</code></pre></div>
<p dir="auto">This assertion error only shows up with Werkzeug version 0.15.3 and 0.15.4. It doesn't appear with version 0.15.2.</p>
<p dir="auto">OS: Pulsar Linux 8.0.0.14<br>
Python: 2.7.9<br>
Flask: 1.0.2</p>