code: def _bracket_exact_var(self, symbol):
          
          if isinstance(self.element, Executable):
              if symbol in self.element.parameters:
                  return self.element.parameters[symbol]            
              if symbol in self.element.members:
                  return self.element.members[symbol]
  
          if symbol in self.element.module.members:
              return self.element.module.members[symbol]
  
          return None
docs: Checks local first and then module global variables for an exact
          match to the specified symbol name.