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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 sanity_check(self, sender, to, subject, plain=None, html=None, cc=None, bcc=None):
 """ Sanity check the message. If we have PLAIN and HTML versions, send a multipart alternative MIME message, else send whichever we do have. If we have neither, raise NoContentError Arguments: - `sender`: str - `to`: list - `subject`: str - `plain`: str - `html`: str Return: None Exceptions: NoContentError """

        if not plain and not html:
            raise NoContentError()