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

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

        array['width'] = int(self.width)  # type int
        array['height'] = int(self.height)  # type int
        if self.thumb is not None:
            array['thumb'] = self.thumb.to_array()  # type PhotoSize

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

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

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

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