code: def unsafe_execute(self, result=None):
          
          if result:
              self.result += result
  
          with opentracing.tracer.start_span(
                  obj=self, child_of=KserSpan.extract_span(self),
                  span_factory=KserSpan) as span:
              self.result = self._onsuccess(self._postrun(self._run()))
              span.obj = self
              return self.result
docs: un-wrapped execution, can raise excepetion
  
          :return: Execution result
          :rtype: kser.result.Result