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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 request(self, method, url, headers=None, body=None):
 """Make a new HTTP request. The *method* argument is the HTTP method as a string, for example ``'GET'`` or ``'POST'``. The *url* argument specifies the URL. The optional *headers* argument specifies extra HTTP headers to use in the request. It must be a sequence of ``(name, value)`` tuples. The optional *body* argument may be used to include a body in the request. It must be a ``bytes`` instance, a file-like object opened in binary mode, or an iterable producing ``bytes`` instances. To send potentially large bodies, use the file or iterator interfaces. This has the benefit that only a single chunk is kept in memory at a time. The response to the request can be obtained by calling the :meth:`getresponse` method. You may make multiple requests before reading a response. For every request that you make however, you must call :meth:`getresponse` exactly once. The remote HTTP implementation will send by the responses in the same order as the requests. This method will use the "chunked" transfer encoding if here is a body and the body size is unknown ahead of time. This happens when the file or interator interface is used in the abence of a "Content-Length" header. """

        if self._error:
            raise compat.saved_exc(self._error)
        elif self._transport is None:
            raise HttpError('not connected')
        request = HttpRequest(self)
        bodylen = -1 if body is None else \
                        len(body) if isinstance(body, bytes) else None
        request.start_request(method, url, headers, bodylen)
        if isinstance(body, bytes):
            request.write(body)
        elif hasattr(body, 'read'):
            while True:
                chunk = body.read(4096)
                if not chunk:
                    break
                request.write(chunk)
        elif hasattr(body, '__iter__'):
            for chunk in body:
                request.write(chunk)
        request.end_request()