'Returns a copy of the operand with the sign inverted.
>>> ExtendedContext.copy_negate(Decimal(\'101.5\'))
Decimal(\'-101.5\')
>>> ExtendedContext.copy_negate(Decimal(\'-101.5\'))
Decimal(\'101.5\')
>>> ExtendedContext.copy_negate(1)
Decimal(\'-1\')'

def copy_negate(self, a):

    a = _convert_other(a, raiseit=True)
    return a.copy_negate()
