docs: def _interception(self, joinpoint):
          """Intercept call of joinpoint callee in doing pre/post conditions.
          """
  
          if self.pre_cond is not None:
              self.pre_cond(joinpoint)
  
          result = joinpoint.proceed()
  
          if self.post_cond is not None:
              joinpoint.exec_ctx[Condition.RESULT] = result
              self.post_cond(joinpoint)
  
          return result