title: Get week of year - expressions and functions in azure data factory
body: <p>I'm pretty new to ADF and I'm trying to parametrise a variable that takes as input year and week of the year; for example, 202042 or 202102</p>
  <p>After digging a bit, I created the below function, but it looks like weekOfYear is not available.</p>
  <p>what is the way to get weekOfYear in ADF?</p>
  <pre><code>@concat('PREFIX',
  formatdatetime(utcnow(), 'yyyy'),
  weekOfYear((formatdatetime(utcnow(), 'yyyyMMdd'))),
  ‘.SUFFIX’)
  </code></pre>