title: Pandas: Merging multiple dataframes efficiently
body: <p>I have a situation where I need to merge multiple dataframes that I can do easily using the below code:</p>
  <pre><code># Merge all the datasets together
  df_prep1 = df_prep.merge(df1,on='e_id',how='left')
  df_prep2 = df_prep1.merge(df2,on='e_id',how='left')
  df_prep3 = df_prep2.merge(df3,on='e_id',how='left')
  df_prep4 = df_prep3.merge(df_4,on='e_id',how='left')
  df_prep5 = df_prep4.merge(df_5,on='e_id',how='left')
  df_prep6 = df_prep5.merge(df_6,on='e_id',how='left')
  </code></pre>
  <p>But what I want to understand is that if there is any other efficient way to perform this merge, maybe using a helper function? If yes, then how could I achieve that?</p>