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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 pandas_dataframe(self, start, stop, ncol, **kwargs):
 """ Returns the result of tab-separated pandas.read_csv on a subset of the file. Args: start (int):
 line number where structured data starts stop (int):
 line number where structured data stops ncol (int or list):
 the number of columns in the structured data or a list of that length with column names Returns: pd.DataFrame: structured data """

        try:
            int(start)
            int(stop)
        except TypeError:
            print('start and stop must be ints')
        try:
            ncol = int(ncol)
            return pd.read_csv(six.StringIO('\n'.join(self[start:stop])), delim_whitespace=True, names=range(ncol), **kwargs)
        except TypeError:
            try:
                ncol = list(ncol)
                return pd.read_csv(six.StringIO('\n'.join(self[start:stop])), delim_whitespace=True, names=ncol, **kwargs)
            except TypeError:
                print('Cannot pandas_dataframe if ncol is {}, must be int or list'.format(type(ncol)))