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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 get_colname(self, colnum):
 """ Get the name associated with the given column number parameters colnum: integer The number for the column, zero offset """

        if colnum < 0 or colnum > (len(self._colnames)-1):
            raise ValueError(
                "colnum out of range [0,%s-1]" % (0, len(self._colnames)))
        return self._colnames[colnum]