(self)
return self.term.is_zero
A Product is zero only if its term is zero.
A Product is zero only if its term is zero.
A Product is zero only if its term is zero .
def is_zero(self):
        """A Product is zero only if its term is zero.
        """
        return self.term.is_zero
def is_zero ( self ) : return self . term . is_zero