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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 set_cols_valign(self, array):
 """Set the desired columns vertical alignment - the elements of the array should be either "t", "m" or "b": * "t": column aligned on the top of the cell * "m": column aligned on the middle of the cell * "b": column aligned on the bottom of the cell """


        self._check_row_size(array)
        self._valign = array
        return self