code: def validate_brain_requirements(connection, remote_dbs, requirements):
      
      for database in requirements:
          assert (database in remote_dbs), "database {} must exist".format(database)
          remote_tables = frozenset(rethinkdb.db(database).table_list().run(connection))
          for table in requirements[database]:
              assert (table in remote_tables), "{} must exist in {}".format(table, database)
      return True
docs: validates the rethinkdb has the 'correct' databases and tables
      should get remote_dbs from brain.connection.validate_get_dbs
  
      :param connection: <rethinkdb.net.DefaultConnection>
      :param remote_dbs: <set> database names present in remote database
      :param requirements: <dict> example(brain.connection.SELF_TEST)
      :return: <bool> True
      :raises: AssertionError or Reql*Error