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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_voms_proxy_user():
 """ Returns the owner of the voms proxy. """

    out = _voms_proxy_info(["--identity"])[1].strip()
    try:
        return re.match(r".*\/CN\=([^\/]+).*", out.strip()).group(1)
    except:
        raise Exception("no valid identity found in voms proxy: {}".format(out))