installing cPickle with python 3.5
<p>This might be silly but I am unable to install <code>cPickle</code> with python 3.5 docker image</p>

<p><strong>Dockerfile</strong></p>

<pre><code>FROM python:3.5-onbuild
</code></pre>

<p><strong>requirements.txt</strong></p>

<pre><code>cpickle
</code></pre>

<p>When I try to build the image</p>

<pre><code>$ docker build -t sample .
Sending build context to Docker daemon 3.072 kB
Step 1 : FROM python:3.5-onbuild
# Executing 3 build triggers...
Step 1 : COPY requirements.txt /usr/src/app/
Step 1 : RUN pip install --no-cache-dir -r requirements.txt
 ---&gt; Running in 016c35a032ee
Collecting cpickle (from -r requirements.txt (line 1))
  Could not find a version that satisfies the requirement cpickle (from -r requirements.txt (line 1)) (from versions: )
No matching distribution found for cpickle (from -r requirements.txt (line 1))
You are using pip version 7.1.2, however version 8.1.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
The command '/bin/sh -c pip install --no-cache-dir -r requirements.txt' returned a non-zero code: 1
</code></pre>