pyqgis - How to change the active layer in QGIS Console?

I want my script to perform actions on a particular layer. Online advice I've found so far suggests using the iface method "setActiveLayer()". Makes sense based on the name alone.

Scenario: In the Layers window I have a layer named "Province" highlighted (active). Then I run the following code:

>>> vl = QgsMapLayerRegistry.instance().mapLayer( 'na_roads_Prov' )
>>> iface.setActiveLayer(vl)

Console Output = False

As far as I understand executing this code in the console should move the highlighted "active layer" from "Province" to 'na_roads_Prov'. Yes? Instead the "Province" layer remains highlighted as active, and the console output says "False". Any ideas? Am I not referring to the layer correctly?

Answer

Use mapLayersByName method to get the layer by name

vl = QgsMapLayerRegistry.instance().mapLayersByName('na_roads_Prov')[0]
iface.setActiveLayer(vl)