According to the 2011 census, what was the population of the municipality in which Erjon Dollapi was born?
Erjon Dollapi: Erjon Dollapi (born 16 March 1993 in Tropojë, Albania) is an Albanian-born English semi-professional rugby league player who currently plays for London Skolars in league 1. Tropojë:  The seat of the municipality is the town Bajram Curri. Tropojë:  The total population is 20,517 (2011 census), in a total area of 1057.30 km.
20,517