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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 set_proxy(proxy_url, transport_proxy=None):
 """Create the proxy to PyPI XML-RPC Server"""

    global proxy, PYPI_URL
    PYPI_URL = proxy_url
    proxy = xmlrpc.ServerProxy(
        proxy_url,
        transport=RequestsTransport(proxy_url.startswith('https://')),
        allow_none=True)