shares_schema = {'crystal_id': {'type': 'objectid', 'required': True,
    'data_relation': {'resource': 'crystals', 'embeddable': True}},
    'user_id': {'type': 'objectid', 'required': True, 'data_relation': {
    'resource': 'users', 'embeddable': True}}}
shares = {'internal_resource': True, 'schema': shares_schema}
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