title: pandas multiple date ranges from column of dates
body: <p>Current df:</p>
  
  <pre><code>ID  Date
  11  3/19/2018
  22  1/5/2018
  33  2/12/2018
  ..  ..
  </code></pre>
  
  <p>I have the df with ID and Date. ID is unique in the original df.
  I would like to create a new df based on date. Each ID has a Max Date, I would like to use that date and go back 4 days(5 rows each ID)
  There are thousands of IDs.</p>
  
  <p>Expect to get:</p>
  
  <pre><code>ID  Date
  11  3/15/2018
  11  3/16/2018
  11  3/17/2018
  11  3/18/2018
  11  3/19/2018
  22  1/1/2018
  22  1/2/2018
  22  1/3/2018
  22  1/4/2018
  22  1/5/2018
  33  2/8/2018
  33  2/9/2018
  33  2/10/2018
  33  2/11/2018
  33  2/12/2018
  …   …
  </code></pre>
  
  <p>I tried the following method, i think use <code>date_range</code> might be right direction, but I keep get error. </p>
  
  <p>pd.date_range</p>
  
  <pre><code>def date_list(row):
      list = pd.date_range(row["Date"], periods=5)
      return list
  
  df["Date_list"] = df.apply(date_list, axis = "columns")
  </code></pre>