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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 _prepare_headers(self, additional_headers=None, **kwargs):
 """Prepare headers for http communication. Return dict of header to be used in requests. Args: .. versionadded:: 0.3.2 **additional_headers**: (optional) Additional headers to be used with request Returns: Headers dict. Key and values are string """

        user_agent = "pyseaweed/{version}".format(version=__version__)
        headers = {"User-Agent": user_agent}
        if additional_headers is not None:
            headers.update(additional_headers)
        return headers