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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_dtype(self, array):
 """Set the desired columns datatype for the cols. - the elements of the array should be either a callable or any of "a", "t", "f", "e" or "i": * "a": automatic (try to use the most appropriate datatype) * "t": treat as text * "f": treat as float in decimal format * "e": treat as float in exponential format * "i": treat as int * a callable: should return formatted string for any value given - by default, automatic datatyping is used for each column """


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