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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_user_variables(self):
 """a public method to help report engines to introspect a template and find what data it needs and how it will be used returns a list of user variable names without starting 'py3o.'"""

        # TODO: Check if some user fields are stored in other content_trees
        return [
            e.get('{%s}name' % e.nsmap.get('text'))[5:]
            for e in get_user_fields(self.content_trees[0], self.namespaces)
        ]