Installation Issues: No matching distribution found for gym (from osim-rl==1.5)

[filipre]

Hi!

I followed the installation guide in the readme. However, I always get following error message:

(opensim-rl) ➜  reinforcement-learning pip install git+https://github.com/stanfordnmbl/osim-rl.git
Collecting git+https://github.com/stanfordnmbl/osim-rl.git
  Cloning https://github.com/stanfordnmbl/osim-rl.git to /private/var/folders/8c/qrh6r14j2wngvdydz5qz4n1j1kz20v/T/pip-3MFaVf-build
Requirement already satisfied: numpy in /Users/d060659/anaconda/envs/opensim-rl/lib/python2.7/site-packages (from osim-rl==1.5)
Collecting gym (from osim-rl==1.5)
/Users/d060659/anaconda/envs/opensim-rl/lib/python2.7/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:318: SNIMissingWarning: An HTTPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. This may cause the server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.html#snimissingwarning.
  SNIMissingWarning
/Users/d060659/anaconda/envs/opensim-rl/lib/python2.7/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
  Could not fetch URL https://pypi.python.org/simple/gym/: There was a problem confirming the ssl certificate: [Errno 1] _ssl.c:504: error:0D0890A1:asn1 encoding routines:ASN1_verify:unknown message digest algorithm - skipping
  Could not find a version that satisfies the requirement gym (from osim-rl==1.5) (from versions: )
No matching distribution found for gym (from osim-rl==1.5)
/Users/d060659/anaconda/envs/opensim-rl/lib/python2.7/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning

Are some requirements missing? Has it to do with SSL? I'm confused because I thought that command was supposed to install gym so why does it say it needs it as requirement?

Issue #32 is related but the author did not issue the pip install command

[kidzik]

Indeed pip install gym should work right away.
It looks like a bug on the PyPI side, related to SSL
pypa/pip#829
https://stackoverflow.com/questions/15441224/can-i-relink-enthought-python-to-new-version-of-openssl-on-mac-os-x

It seems that --allow-all-external --allow-unverified might help, but it's not ideal. There are a few other suggestions there though.