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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def start_step(self, lineno, name="Unnamed step", timestamp=None):
 """Create a new step and update the state to reflect we're now in the middle of a step."""

        self.state = self.STATES['step_in_progress']
        self.stepnum += 1
        self.steps.append({
            "name": name,
            "started": timestamp,
            "started_linenumber": lineno,
            "errors": [],
        })