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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 shift(self, shifts=None, fill_value=dtypes.NA, **shifts_kwargs):
 """ Return a new Variable with shifted data. Parameters shifts : mapping of the form {dim: offset} Integer offset to shift along each of the given dimensions. Positive offsets shift to the right; negative offsets shift to the left. fill_value: scalar, optional Value to use for newly missing values **shifts_kwargs: The keyword arguments form of ``shifts``. One of shifts or shifts_kwarg must be provided. Returns ------- shifted : Variable Variable with the same dimensions and attributes but shifted data. """

        shifts = either_dict_or_kwargs(shifts, shifts_kwargs, 'shift')
        result = self
        for dim, count in shifts.items():
            result = result._shift_one_dim(dim, count, fill_value=fill_value)
        return result