title: Python - Iterate through multiple dataframes and append data to a new dataframe
body: <p>I have 3 pandas dataframes. I would like to append one row from each in each iteration to an existing dataframe.</p>
  <p>Example shown below:</p>
  <pre><code>DF1 =
  
  col1 col2 col3
  a     a    a
  d     d    d
  g     g    g
  
  </code></pre>
  <pre><code>DF2=
  
  col1 col2 col3
  b     b    b
  e     e    e
  h     h    h
  
  </code></pre>
  <pre><code>DF3=
  
  col1 col2 col3
  c     b    b
  f     f    f
  i     i    i
  
  </code></pre>
  <pre><code>clean_DF =
  
  col1 col2 col3
  a     a    a
  b     b    b 
  c     c    c
  d     d    d
  e     e    e
  f     f    f
  g     g    g
  h     h    h 
  i     i    i
  </code></pre>
  <p>Dummy code:</p>
  <pre><code>for i,j in df1.itterows():
     for a,b in df2.itterows():
         for c,d in df2.itterrows():
  clean_df.append(i,j,a,b,c,d)
  </code></pre>
  <p>Please could someone point me in the right direction?</p>