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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 _parse_wsgi_headers(wsgi_environ):
 """ HTTP headers are presented in WSGI environment with 'HTTP_' prefix. This method finds those headers, removes the prefix, converts underscores to dashes, and converts to lower case. :param wsgi_environ: :return: returns a dictionary of headers """

        prefix = 'HTTP_'
        p_len = len(prefix)
        # use .items() despite suspected memory pressure bc GC occasionally
        # collects wsgi_environ.iteritems() during iteration.
        headers = {
            key[p_len:].replace('_', '-').lower():
                val for (key, val) in wsgi_environ.items()
            if key.startswith(prefix)}
        return headers