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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, periods, axis=0, fill_value=None):
 """ shift the block by periods, possibly upcast """


        # convert integer to float if necessary. need to do a lot more than
        # that, handle boolean etc also
        new_values, fill_value = maybe_upcast(self.values, fill_value)

        # make sure array sent to np.roll is c_contiguous
        f_ordered = new_values.flags.f_contiguous
        if f_ordered:
            new_values = new_values.T
            axis = new_values.ndim - axis - 1

        if np.prod(new_values.shape):
            new_values = np.roll(new_values, ensure_platform_int(periods),
                                 axis=axis)

        axis_indexer = [slice(None)] * self.ndim
        if periods > 0:
            axis_indexer[axis] = slice(None, periods)
        else:
            axis_indexer[axis] = slice(periods, None)
        new_values[tuple(axis_indexer)] = fill_value

        # restore original order
        if f_ordered:
            new_values = new_values.T

        return [self.make_block(new_values)]