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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 require_representation(self, req):
 """Require raw representation dictionary from falcon request object. This does not perform any field parsing or validation but only uses allowed content-encoding handler to decode content body. Note: Currently only JSON is allowed as content type. Args: req (falcon.Request):
 request object Returns: dict: raw dictionary of representation supplied in request body """

        try:
            type_, subtype, _ = parse_mime_type(req.content_type)
            content_type = '/'.join((type_, subtype))
        except:
            raise falcon.HTTPUnsupportedMediaType(
                description="Invalid Content-Type header: {}".format(
                    req.content_type
                )
            )

        if content_type == 'application/json':
            body = req.stream.read()
            return json.loads(body.decode('utf-8'))
        else:
            raise falcon.HTTPUnsupportedMediaType(
                description="only JSON supported, got: {}".format(content_type)
            )