code: def pandas_dataframe_to_unit_arrays(df, column_units=None):
      
      if not column_units:
          try:
              column_units = df.units
          except AttributeError:
              raise ValueError('No units attribute attached to pandas '
                               'dataframe and col_units not given.')
  
      # Iterate through columns attaching units if we have them, if not, don't touch it
      res = {}
      for column in df:
          if column in column_units and column_units[column]:
              res[column] = df[column].values * units(column_units[column])
          else:
              res[column] = df[column].values
      return res
docs: Attach units to data in pandas dataframes and return united arrays.
  
      Parameters
      ----------
      df : `pandas.DataFrame`
          Data in pandas dataframe.
  
      column_units : dict
          Dictionary of units to attach to columns of the dataframe. Overrides
          the units attribute if it is attached to the dataframe.
  
      Returns
      -------
          Dictionary containing united arrays with keys corresponding to the dataframe
          column names.