Bug 2102371

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Version:

$ openshift-install version
4.11

Platform:

#Please specify the platform type: aws, libvirt, openstack or baremetal etc.
gcp

Please specify:
* IPI (automated install with `openshift-install`. If you don't know, then it's IPI)
* UPI (semi-manual installation on customized infrastructure)
IPI

What happened?

#Enter text here.
The GCP/hosts.py script was updated to python3 and the requirements for running the script are missing as well as documentation on how to use the script.

The missing packages include: pycrypto >= 2.6, apache-libcloud.

**Note: pycrypto may not be necessary. 

#See the troubleshooting documentation (https://github.com/openshift/installer/blob/master/docs/user/troubleshooting.md) for ideas about what information to collect.

There is no troubleshooting documentation or documentation at all in this directory. Clean this up by adding documentation about the script as well as some of the required and option environment variables used through out the script.

REQUIRED:
GCE_EMAIL
GCE_PEM_FILE_PATH

OPTIONAL:
GCE_PROJECT
GCE_ZONE
GCE_INI_PATH
GCE_TAGGED_INSTANCES
INVENTORY_IP_TYPE

# If the installer fails to create resources (https://github.com/openshift/installer/blob/master/docs/user/troubleshooting.md#installer-fails-to-create-resources), attach the relevant portions of your `.openshift_install.log.`
# If the installer fails to bootstrap the cluster (https://github.com/openshift/installer/blob/master/docs/user/troubleshootingbootstrap.md), attach the bootstrap log bundle.
# If the installer fails to complete installation after bootstrapping completes (https://github.com/openshift/installer/blob/master/docs/user/troubleshooting.md#installer-fails-to-initialize-the-cluster), attach the must-gather log bundle using `oc adm must-gather`

# Always at least include the `.openshift_install.log`

What did you expect to happen?

Ability to execute the hosts.py script

How to reproduce it (as minimally and precisely as possible)?

$ your-commands-here

python (updates to python3) hosts.py 

Anything else we need to know?

#Enter text here.