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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 get_all_mfa_devices(user_name, region=None, key=None, keyid=None,
                        profile=None):
    '''
    Get all MFA devices associated with an IAM user.

    .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt myminion boto_iam.get_all_mfa_devices user_name
    '''
    user = get_user(user_name, region, key, keyid, profile)
    if not user:
        log.error('IAM user %s does not exist', user_name)
        return False
    conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)
    try:
        result = conn.get_all_mfa_devices(user_name)
        devices = result['list_mfa_devices_response']['list_mfa_devices_result']['mfa_devices']
        return devices
    except boto.exception.BotoServerError as e:
        log.debug(e)
        if 'Not Found' in e:
            log.info('Could not find IAM user %s.', user_name)
            return []
        log.error('Failed to get all MFA devices for IAM user %s.', user_name)
        return False