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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_key_id(alias, region=None, key=None, keyid=None, profile=None):
    '''
    From an alias, get a key_id.
    '''
    key_metadata = describe_key(
        alias, region, key, keyid, profile
    )['key_metadata']
    return key_metadata['KeyId']