def __init__(self, doc):
    '\n        Initialize from a database document.\n\n        :param dict doc: A database document.\n        '
    if ('usage' not in doc):
        _invalid('Robots.txt usage is required')
    self._usage = doc['usage']
Initialize from a database document.

:param dict doc: A database document.
def __init__(self, doc):
    '\n        Initialize from a database document.\n\n        :param dict doc: A database document.\n        '
    if ('usage' not in doc):
        _invalid('Robots.txt usage is required')
    self._usage = doc['usage']