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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 get_query_string(environ):
 """Returns the `QUERY_STRING` from the WSGI environment. This also takes care about the WSGI decoding dance on Python 3 environments as a native string. The string returned will be restricted to ASCII characters. .. versionadded:: 0.9 :param environ: the WSGI environment object to get the query string from. """

    qs = wsgi_get_bytes(environ.get("QUERY_STRING", ""))
    # QUERY_STRING really should be ascii safe but some browsers
    # will send us some unicode stuff (I am looking at you IE).
    # In that case we want to urllib quote it badly.
    return try_coerce_native(url_quote(qs, safe=":&%=+$!*'(),"))