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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 types_(self, col: str) -> pd.DataFrame: """ Display types of values in a column :param col: column name :type col: str :return: a pandas dataframe :rtype: pd.DataFrame :example: ``ds.types_("Col 1")`` """

        cols = self.df.columns.values
        all_types = {}
        for col in cols:
            local_types = []
            for i, val in self.df[col].iteritems():
                #print(i, val, type(val))
                t = type(val).__name__
                if t not in local_types:
                    local_types.append(t)
            all_types[col] = (local_types, i)
        df = pd.DataFrame(all_types, index=["type", "num"])
        return df