context: Tranmere started season 2016/17 brightly, top of the table at the end of August, gaining Gary Brabin the manager of the month.  However, form dipped which resulted in one goal scored in the next four games, with the 1-0 defeat to Sutton United on BT Sport resulting in Brabin being sacked on 18 September 2016.  Assistant manager, ex-Southport boss Paul Carden took the reins on an interim basis. On 6 October 2016, however, former Tranmere player Micky Mellon was appointed permanent manager. His first game in charge was against cross-border rivals Wrexham AFC, and a 2-0 victory for Tranmere.  Despite a 2nd-place finish and a club record 95 point haul, this still was not enough to gain automatic promotion back to the league.  Tranmere faced Aldershot Town in the playoffs.  A goal from James Norwood and a brace from Cole Stockton in the first leg away at the Recreation Ground (Aldershot) saw Rovers take a 3-0 aggregate lead back to Prenton Park for the second leg, which ended in a 2-2 draw, Norwood and Stockton once again on the scoresheet. This gave Tranmere a 5-2 aggregate win and their first Wembley appearance in 17 years.  On 14 May 2017, Tranmere suffered a 3-1 defeat in the Vanarama National League play-off final at the hands of Forest Green Rovers, Connor Jennings with Rovers first goal at Wembley since the 2000 Football League Cup Final.
question: How many weeks did it take Tranmere to find a permanent coach after firing Brabin?
answer: 3