def is_valid(self):
    self.calc_sha256()
    for tout in self.vout:
        if ((tout.nValue < 0) or (tout.nValue > (21000000 * COIN))):
            return False
    return True
def is_valid(self):
    self.calc_sha256()
    for tout in self.vout:
        if ((tout.nValue < 0) or (tout.nValue > (21000000 * COIN))):
            return False
    return True