Conda 'ImportError: No module named ruamel.yaml.comments'
<p>Conda gives error when I run any command with it.</p>

<pre><code>Traceback (most recent call last):
  File "/usr/local/bin/conda", line 7, in &lt;module&gt;
    from conda.cli.main import main
  File "/usr/local/lib/python2.7/dist-packages/conda/cli/__init__.py", line 8, in &lt;module&gt;
    from .main import main  # NOQA
  File "/usr/local/lib/python2.7/dist-packages/conda/cli/main.py", line 46, in &lt;module&gt;
    from ..base.context import context
  File "/usr/local/lib/python2.7/dist-packages/conda/base/context.py", line 18, in &lt;module&gt;
    from ..common.configuration import (Configuration, MapParameter, PrimitiveParameter,
  File "/usr/local/lib/python2.7/dist-packages/conda/common/configuration.py", line 40, in &lt;module&gt;
    from ruamel.yaml.comments import CommentedSeq, CommentedMap  # pragma: no cover
ImportError: No module named ruamel.yaml.comments
</code></pre>