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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(pypi_server):
 """ Query the PyPI RSS feed and return a list of XML items. """

    response = requests.get(pypi_server)
    if response.status_code >= 300:
        raise HTTPError(status_code=response.status_code,
                        reason=response.reason)
    if hasattr(response.content, 'decode'):
        tree = xml.etree.ElementTree.fromstring(response.content.decode())
    else:
        tree = xml.etree.ElementTree.fromstring(response.content)
    channel = tree.find('channel')
    return channel.findall('item')