code: def get_sample(df,n):
      
      idxs = sorted(np.random.permutation(len(df))[:n])
      return df.iloc[idxs].copy()
docs: Gets a random sample of n rows from df, without replacement.
      Parameters:
      -----------
      df: A pandas data frame, that you wish to sample from.
      n: The number of rows you wish to sample.
      Returns:
      --------
      return value: A random sample of n rows of df.
      Examples:
      ---------
      >>> df = pd.DataFrame({'col1' : [1, 2, 3], 'col2' : ['a', 'b', 'a']})
      >>> df
         col1 col2
      0     1    a
      1     2    b
      2     3    a
      >>> get_sample(df, 2)
         col1 col2
      1     2    b
      2     3    a