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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_window(self, other=None):
 """ Get the window length over which to perform some operation. Parameters other : object, default None The other object that is involved in the operation. Such an object is involved for operations like covariance. Returns ------- window : int The window length. """

        axis = self.obj._get_axis(self.axis)
        length = len(axis) + (other is not None) * len(axis)

        other = self.min_periods or -1
        return max(length, other)