title: Pandas: Create new column based on mapped values from another column
body: <p>I want to create a new column based on conditions from another one in Python. More specifically, one of my columns in the dataframe is:</p>
  
  <pre><code>Kilos:
  1. 8.0
  2. 16.0
  3. 12.0
  4. 10.0
  5. 5.0
  ...
  </code></pre>
  
  <p>I want the new column to be based on this column and every time you find a row (in the <code>kilos</code> column) where the kilos are 8.0, then the new's column row will write 'X2 + parts' and when the column is 16.0 the row of the new column will write 'X8 + parts', for the other columns I don't care. They can be blank or anything else.</p>