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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 envs():
    '''
    Each container configuration can have an environment setting, or defaults
    to base
    '''
    saltenvs = []
    for container in __opts__.get('azurefs', []):
        saltenvs.append(container.get('saltenv', 'base'))
    # Remove duplicates
    return list(set(saltenvs))