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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 set_content_type(self):
 """ Set the content type based on the file extension used in the object name. """

        if self.object_name and not self.content_type:
            # XXX nothing is currently done with the encoding... we may
            # need to in the future
            self.content_type, encoding = mimetypes.guess_type(
                self.object_name, strict=False)