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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 Chat to a dictionary. :return: dictionary representation of this object. :rtype: dict """

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

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

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

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

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

        if self.all_members_are_administrators is not None:
            array['all_members_are_administrators'] = bool(self.all_members_are_administrators)  # type bool
        if self.photo is not None:
            array['photo'] = self.photo.to_array()  # type ChatPhoto

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

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

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

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

        if self.can_set_sticker_set is not None:
            array['can_set_sticker_set'] = bool(self.can_set_sticker_set)  # type bool
        return array