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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 _sanity_check(self):
 """ Check if there are enough data points. """

        windows = self.lag_window_size + self.future_window_size
        if (not self.lag_window_size or not self.future_window_size or self.time_series_length < windows or windows < DEFAULT_BITMAP_MINIMAL_POINTS_IN_WINDOWS):
            raise exceptions.NotEnoughDataPoints

        # If window size is too big, too many data points will be assigned a score of 0 in the first lag window
        # and the last future window.
        if self.lag_window_size > DEFAULT_BITMAP_MAXIMAL_POINTS_IN_WINDOWS:
            self.lag_window_size = DEFAULT_BITMAP_MAXIMAL_POINTS_IN_WINDOWS
        if self.future_window_size > DEFAULT_BITMAP_MAXIMAL_POINTS_IN_WINDOWS:
            self.future_window_size = DEFAULT_BITMAP_MAXIMAL_POINTS_IN_WINDOWS