title: Creating a sequence of dataframes
body: <p>a quick question.<br>
  I want to know if there is a way to create a sequence of data frames, by setting a variable inside the name of a data frame. For example:</p>
  
  <pre><code>df_0 = pd.read_csv(file1, sep =',')
  
  b=0
  x=1
  while (b == 0):
      df_+str(x) = pd.merge(df_+str(x-1) , Source, left_on='R_Key', right_on = 'S_Key', how='inner')
  
      if Final_+str(x).empty != 'True':
          x = x + 1
      else:
          b = b + 1
  </code></pre>
  
  <p>Now when executed, this returns "can't assign to operator" for <strong>df_+str(x)</strong>. Any idea how to fix this?</p>