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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 to_array(self):
 """ Serializes this MessageEntity to a dictionary. :return: dictionary representation of this object. :rtype: dict """

        array = super(MessageEntity, self).to_array()
        array['type'] = u(self.type)  # py2: type unicode, py3: type str

        array['offset'] = int(self.offset)  # type int
        array['length'] = int(self.length)  # type int
        if self.url is not None:
            array['url'] = u(self.url)  # py2: type unicode, py3: type str

        if self.user is not None:
            array['user'] = self.user.to_array()  # type User

        return array