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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 sample(self, num_rows):
 """Sample new rows. Args: num_rows(int):
 Number of rows to sample Returns: pandas.DataFrame """


        sampled_values = []
        for i in range(num_rows):
            sampled_values.append(self._sample_row())

        return pd.DataFrame(sampled_values, columns=self.columns)