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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 describe(self, *cols):
 """Computes basic statistics for numeric and string columns. This include count, mean, stddev, min, and max. If no columns are given, this function computes statistics for all numerical or string columns. .. note:: This function is meant for exploratory data analysis, as we make no guarantee about the backward compatibility of the schema of the resulting DataFrame. |summary| age| | count| 2| | mean| 3.5| | stddev|2.1213203435596424| | min| 2| | max| 5| |summary| age| name| | count| 2| 2| | mean| 3.5| null| | stddev|2.1213203435596424| null| | min| 2|Alice| | max| 5| Bob| Use summary for expanded statistics and control over which statistics to compute. """

        if len(cols) == 1 and isinstance(cols[0], list):
            cols = cols[0]
        jdf = self._jdf.describe(self._jseq(cols))
        return DataFrame(jdf, self.sql_ctx)