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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 get_time(self, idx):
 """Return time of data at index `idx` Returns nan if the time is not defined"""

        # raw data
        qpi = self.get_qpimage_raw(idx)
        if "time" in qpi.meta:
            thetime = qpi.meta["time"]
        else:
            thetime = np.nan
        return thetime