docs: def convert_op(self, op):
          """
          Converts NeuroML arithmetic/logical operators to python equivalents.
  
          @param op: NeuroML operator
          @type op: string
  
  
          @return: Python operator
          @rtype: string
          """
  
          if op == '.gt.':
              return '>'
          elif op == '.ge.' or op == '.geq.':
              return '>='
          elif op == '.lt.':
              return '<'
          elif op == '.le.':
              return '<='
          elif op == '.eq.':
              return '=='
          elif op == '.neq.':   
              return '!='
          elif op == '.ne.':   # .neq. is preferred!
              return '!='
          elif op == '^':
              return '**'
          elif op == '.and.':
              return 'and'
          elif op == '.or.':
              return 'or'
          else:
              return op