def __init__(self, id=None, tags=None):
    required = {'id': False, 'tags': False}
    self.id = id
    self.tags = tags
    for (k, v) in required.items():
        if ((self[k] is None) and v):
            raise ValueError('attribute {} is required'.format(k))
def __init__(self, id=None, tags=None):
    required = {'id': False, 'tags': False}
    self.id = id
    self.tags = tags
    for (k, v) in required.items():
        if ((self[k] is None) and v):
            raise ValueError('attribute {} is required'.format(k))