title: Extracting unique list of strings from Python Dataframe column
body: <p>I have an example dataframe as given below:</p>
  
  <pre><code>df = 
  index                Value     Name         
  2019-01-01 07:53:53  10   S_1.M_01
  2019-01-01 08:33:52  20   S_1.M_02
  2019-01-01 09:13:52  30   S_1.M_03
  2019-01-01 09:53:52  40   S_1.M_01
  2019-01-01 10:33:52  50   S_1.M_02
  2019-01-01 11:13:53  60   S_1.M_03                                                                     
  ...  ...       ...
  2019-09-08 15:38:52  100  8157_S2
  </code></pre>
  
  <p>Now I want to extract to those columns with name <code>Name</code> and create outputs. How to extract those rows with same names?</p>
  
  <p>My code: </p>
  
  <pre><code>df_grp = iv_df['element'].unique
  </code></pre>
  
  <p>This did not yield any result. </p>
  
  <p>I want to achieve something like this below different outputs </p>
  
  <p>Output1: </p>
  
  <pre><code>index                Value     Name         
  2019-01-01 07:53:53  10   S_1.M_01
  2019-01-01 09:53:52  40   S_1.M_01
  </code></pre>
  
  <p>Output2: </p>
  
  <pre><code>index                Value     Name         
  2019-01-01 08:33:52  20   S_1.M_02
  2019-01-01 10:33:52  50   S_1.M_02
  </code></pre>
  
  <p>Output3: </p>
  
  <pre><code>index                Value     Name         
  2019-01-01 09:13:52  30   S_1.M_03
  2019-01-01 11:13:53  60   S_1.M_03    
  </code></pre>
  
  <p>How to achieve this?</p>