title: extracting the data from a column in pandas dataframe using regular expression
body: <p>I have a dataframe <code>df</code> as defined below</p>
  
  <pre><code>import pandas as pd
  df = pd.DataFrame(
      {
          "ID": [1, 2, 3, 4, 5],
          "name": [
              "Hello Kitty how=1234 when=2345",
              "how=3456 Hello Puppy when=7685",
              "how=646 It is an Helloexample when=9089",
              "for how=6574 stackoverflow when=5764",
              "Hello  when=3632 World how=7654",
          ],
      }
  )
  
  
  
  
  
  df
  Out[100]: 
     ID                                     name
  0   1           Hello Kitty how=1234 when=2345
  1   2           how=3456 Hello Puppy when=7685
  2   3  how=646 It is an Helloexample when=9089
  3   4     for how=6574 stackoverflow when=5764
  4   5           Hello  when=3632 World how=7654
  </code></pre>
  
  <p>I want to extract the values written that are after <code>how</code> and <code>when</code> into  two separate columns how and when. How can I do the same using regular expression ?</p>
  
  <p>For example: in first record I should get <code>1234</code> in column <code>how</code> and <code>2345</code> in column <code>when</code>. In last record I should get <code>7654</code> in column <code>how</code> and <code>3632</code> in column <code>when</code></p>