title: Extend a data frame using another table in R
body: <p>I have a data frame as following</p>
  <pre><code>df &lt;- data.frame(id = c(12345,12345,12345,221,221,221),
                   range_key = c('w232022','w242022','w252022','w232022','w242022','w252022'),
                   country = c('US','US','US','CA','CA','CA'),
                   case = c('A','B','A','A','B','B')) 
  </code></pre>
  <p>and another data frame which extend of weeks :</p>
  <pre><code>extended_week &lt;- data.frame(range_key=c('w262022','w272022','w282022',...,'w522026'))
  </code></pre>
  <p>I want to add extend_week into the first data frame
  group by (id, country, case)
  The final table looks like  follows:</p>
  <pre><code>id.   range_key country  case
  12345.  w232022. US.      A
  ...     .....    ...      ...
  12345.  W522026. US.      A
  </code></pre>
  <p>Means that each group extend to w52 year 2026.</p>