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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 check_due(self):
 """Check if the last execution of this crawler is older than the scheduled interval."""

        if self.disabled:
            return False
        if self.is_running:
            return False
        if self.delta is None:
            return False
        last_run = self.last_run
        if last_run is None:
            return True
        now = datetime.utcnow()
        if now > last_run + self.delta:
            return True
        return False