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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 _fetch_remote_file(service_url, params=None, use_http_post=False):
 """Retrieves a file from a URL. Returns a tuple (mimetype, filename, data) """

    if not params:
        params = {}

    request_url, response = _fetch_remote(service_url, params, use_http_post)
    dummy, params = cgi.parse_header(
            response.headers.get('Content-Disposition', ''))
    fn = params['filename']

    return (response.headers.get('content-type'),
            fn, response.read(), response.geturl())