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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 strip_cols(self):
 """ Remove leading and trailing white spaces in columns names :example: ``ds.strip_cols()`` """

        cols = {}
        skipped = []
        for col in self.df.columns.values:
            try:
                cols[col] = col.strip()
            except Exception:
                skipped.append(str(col))
        self.df = self.df.rename(columns=cols)
        self.ok("White spaces removed in columns names")
        if len(skipped) > 0:
            self.info("Skipped columns", ','.join(
                skipped), "while removing white spaces")