import re
xml = '''\
<Emp>
<Name>Raja</Name>
<Location>
<city>ABC</city>
<geocode>123</geocode>
<state>XYZ</state>
</Location>
<sal>100</sal>
<type>temp</type>
</Emp>'''
locUpdate = '''\
<Location isupdated=1>
<city>MyCity</city>
<geocode>10.12</geocode>
<state>MyState</state>
</Location>'''
output = re.sub(r"(?s)<Location>.*?</Location>", r"%s" % locUpdate, xml)
print output
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