code: def start_step(self, lineno, name="Unnamed step", timestamp=None):
          
          self.state = self.STATES['step_in_progress']
          self.stepnum += 1
          self.steps.append({
              "name": name,
              "started": timestamp,
              "started_linenumber": lineno,
              "errors": [],
          })
docs: Create a new step and update the state to reflect we're now in the middle of a step.