<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def prepare_request_uri_query(oauth_params, uri):
 """Prepare the Request URI Query. Per `section 3.5.3`_ of the spec. .. _`section 3.5.3`: https://tools.ietf.org/html/rfc5849#section-3.5.3 """

    # append OAuth params to the existing set of query components
    sch, net, path, par, query, fra = urlparse(uri)
    query = urlencode(
        _append_params(oauth_params, extract_params(query) or []))
    return urlunparse((sch, net, path, par, query, fra))