docs: def contains(self, value, equality_comparer=operator.eq):
          '''Determines whether the sequence contains a particular value.
  
          Execution is immediate. Depending on the type of the sequence, all or
          none of the sequence may be consumed by this operation.
  
          Note: This method uses immediate execution.
  
          Args:
              value: The value to test for membership of the sequence
  
          Returns:
              True if value is in the sequence, otherwise False.
  
          Raises:
              ValueError: If the Queryable has been closed.
  
          '''
          if self.closed():
              raise ValueError("Attempt to call contains() on a "
                               "closed Queryable.")
  
          if not is_callable(equality_comparer):
              raise TypeError("contains() parameter equality_comparer={0} is "
                  "not callable".format(repr(equality_comparer)))
  
          if equality_comparer is operator.eq:
              return value in self._iterable
  
          for item in self:
              if equality_comparer(value, item):
                  return True
          return False