title: rename column name index according to list placement with multiple duplicate names
body: <p>I just asked a similar question <a href="https://stackoverflow.com/questions/69799025/rename-columns-according-to-list">rename columns according to list</a> which has a correct answer for how to add suffixes to column names correctly. But i have a new issue. I want to rename the actual index name for the columns per dataframe. I have three lists of data frames (some of the data frames contain duplicate column index names (and actual data frame names as well - but thats not the issue, the issue is the duplicated original column.names). I simply want to append a suffix to each dataframe.column.name within each list, with a name in the suffix list, based on its numeric order.</p>
  <p>here is an example of the data and the output i would like:</p>
  <pre><code># add string to end of x in list of dfs
  
  df1, df2, df3, df4 = (pd.DataFrame(np.random.randint(0,10,size=(10, 2)), columns=('a', 'b')), 
                        pd.DataFrame(np.random.randint(0,10,size=(10, 2)), columns=('c', 'd')),
                        pd.DataFrame(np.random.randint(0,10,size=(10, 2)), columns=('e', 'f')),
                        pd.DataFrame(np.random.randint(0,10,size=(10, 2)), columns=('g', 'h')))
  
  df1.columns.name = 'abc'
  df2.columns.name = 'abc'
  df3.columns.name = 'efg'
  df4.columns.name = 'abc'
  
  cat_a = [df2, df1]
  cat_b = [df3, df2, df1]
  cat_c = [df1]
  
  
  dfs = [cat_a, cat_b, cat_c]
  suffix = ['group1', 'group2', 'group3']
  
  # expected output = 
  #for df in cat_a: df.columns.name = df.columns.name + 'group1'
  #for df in cat_b: df.columns.name = df.columns.name + 'group2'   
  #for df in cat_c: df.columns.name = df.columns.name + 'group3' 
  
  </code></pre>
  <p>and here is some code that i have written that doesn't work - where df.column.names are duplicated across data frames, multiple suffixes are appended</p>
  <pre><code>for x, df in enumerate(dfs):
      for i in df:
          n = ([(i.columns.name + '_' + str(suffix[x])) for out in i.columns.name])
          i.columns.name=n[x]
  </code></pre>
  <p>thank you for looking, i really appreciate it</p>