`az storage blob exists` Fails

[poita66]

Describe the bug

Command Name
az storage blob exists

Errors:

No module named '_cffi_backend'
Traceback (most recent call last):
python3.6/site-packages/knack/cli.py, ln 215, in invoke
    cmd_result = self.invocation.execute(args)
cli/core/commands/__init__.py, ln 553, in execute
    self.commands_loader.load_arguments(command)
azure/cli/core/__init__.py, ln 478, in load_arguments
    self.command_table[command].load_arguments()  # this loads the arguments via reflection
cli/core/commands/__init__.py, ln 310, in load_arguments
    super(AzCliCommand, self).load_arguments()
...
storage/v2018_11_09/blob/_encryption.py, ln 13, in <module>
    from cryptography.hazmat.primitives.padding import PKCS7
cryptography/hazmat/primitives/padding.py, ln 13, in <module>
    from cryptography.hazmat.bindings._padding import lib
ModuleNotFoundError: No module named '_cffi_backend'

To Reproduce:

Steps to reproduce the behavior. Note that argument values have been redacted, as they may contain sensitive information.

• Enter registry.fedoraproject.org/f32/fedora-toolbox:32 container with podman (docker may also work)
• Install Azure CLI by following https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-yum
• az login
• az storage blob exists --container-name {} --name {} --account-name {}

Expected Behavior

A valid response describing if the blob exists

Environment Summary

Linux-5.8.16-200.fc32.x86_64-x86_64-with-glibc2.2.5
Python 3.8.6
Installer: RPM

azure-cli 2.13.0

Additional Context

• This is running in fedora-toolbox:32 container (registry.fedoraproject.org/f32/fedora-toolbox:32)
• Azure CLI installed by following https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-yum
• Other commands (e.g. az group create) work as expected

[yonzhan]

add to S178

[Juliehzl]

See here https://github.com/Azure/azure-cli/blob/dev/doc/install_troubleshooting.md#errors-on-install-with-cffi-or-cryptography.
sudo yum install -y python3-cffi