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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 _split_docker_uuid(uuid):
    '''
    Split a smartos docker uuid into repo and tag
    '''
    if uuid:
        uuid = uuid.split(':')
        if len(uuid) == 2:
            tag = uuid[1]
            repo = uuid[0]
            return repo, tag
    return None, None