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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def list_envs():
 """List all environments"""

    for env in lib.get_environments():
        margin_left = lib.get_margin(len(env['name']))
        print("{0}{1}{2}".format(
            env['name'], margin_left,
            env.get('description', '(no description)')))