code: def visit_Name(self, node):
          
          if (isinstance(node.ctx, ast.Load) and
                  node.id not in self.local_decl and
                  node.id in self.to_expand):
              self.update = True
              return ast.Call(func=node,
                              args=[], keywords=[])
          return node
docs: Turn global variable used not shadows to function call.
  
          We check it is a name from an assignment as import or functions use
          should not be turn into call.