'Test whether self and other have the same exponent.
same as self._exp == other._exp, except NaN == sNaN'

def same_quantum(self, other):

    if (self._is_special or other._is_special):
        if (self._isnan() or other._isnan()):
            return (self._isnan() and other._isnan() and True)
        if (self._isinfinity() or other._isinfinity()):
            return (self._isinfinity() and other._isinfinity() and True)
    return (self._exp == other._exp)
