Create script for deleting duplicates

I need bash or python script to delete duplicates into .xml file
For example i have a .xml file and into this file have a lot of duplicates like bellow format , as you see i have a duplicates <fullName>NAME1</fullName> i need to delete it with script but i have a i point into .xml there may be several picklists, which under this picklist can have such values like <fullName>NAME1</fullName> it is necessary that the script does not remove <fullName>NAME1</fullName> from in every picklist

<picklistValues>
<picklist>PICKLIST_VALUE</picklist>
<values>
<fullName>NAME1/fullName>
<default>false</default>
</values>
<values>
<fullName>NAME2</fullName>
<default>false</default>
</values>
<values>
<fullName>NAME3</fullName>
<default>false</default>
</values>
<values>
<fullName>NAME1</fullName>
<default>false</default>
</values>
<values>
<fullName>NAME4</fullName>
<default>false</default>
</values>