title: cannot call value of non-functional type 'DispatchQueue'
body: <p>After converting to swift 3 i found got this error kindly someone let me know whats the solution for this cannot call value of non-functional type 'DispatchQueue'<a href="https://i.stack.imgur.com/dVOua.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dVOua.png" alt="enter image description here" /></a></p>
  <p>Thank You</p>