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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 validate(self):
 """ Checks if message is valid and raises appropriate exception. """


        if not (self.recipients or self.cc or self.bcc):
            raise InvalidMessage("No recipients have been added")

        if not self.body and not self.html:
            raise InvalidMessage("No body has been set")

        if not self.sender:
            raise InvalidMessage("No sender address has been set")

        if self.is_bad_headers():
            raise BadHeaders