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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 _get_content_type(self, file):
 """ Return content type of file. If file does not have a content type, make a guess. """

        if file.mimetype:
            return file.mimetype

        # get file extension
        _, extension = os.path.splitext(file.name)
        extension = extension.strip('.')

        # Make an educated guess about what the Content-Type should be.
        return media_types[extension] if extension in media_types else 'binary/octet-stream'