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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_data(self, data: AnyStr) -> None: """Set the response data. This will encode using the :attr:`charset`. """

        if isinstance(data, str):
            bytes_data = data.encode(self.charset)
        else:
            bytes_data = data
        self.response = self.data_body_class(bytes_data)
        if self.automatically_set_content_length:
            self.content_length = len(bytes_data)