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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def space(self):
 """Combined Hilbert space of all matrix elements."""

        arg_spaces = [o.space for o in self.matrix.ravel()
                      if hasattr(o, 'space')]
        if len(arg_spaces) == 0:
            return TrivialSpace
        else:
            return ProductSpace.create(*arg_spaces)