SettingWithCopyWarning in Core\Indexing.py
  The code I ran looked something like the below

df.loc[:, 'A'] = df['A'] \* (df['B'] / df['C'])

  and I received a warning from within Pandas

...\pandas\core\indexing.py:385: SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_index,col_indexer] = value instead
  self.obj[item] = s
