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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 parse_free_space_response(content, hostname):
 """Parses of response content XML from WebDAV server and extract an amount of free space. :param content: the XML content of HTTP response from WebDAV server for getting free space. :param hostname: the server hostname. :return: an amount of free space in bytes. """

        try:
            tree = etree.fromstring(content)
            node = tree.find('.//{DAV:}quota-available-bytes')
            if node is not None:
                return int(node.text)
            else:
                raise MethodNotSupported(name='free', server=hostname)
        except TypeError:
            raise MethodNotSupported(name='free', server=hostname)
        except etree.XMLSyntaxError:
            return str()