fix silly syntax error

wholmgren · wholmgren · commit 63da5e6962e0 · 2016-01-30T22:00:38.000-07:00
diff --git a/pvlib/location.py b/pvlib/location.py
@@ -228,7 +228,7 @@ def get_airmass(self, times=None, solar_position=None,
             zenith = solar_position['apparent_zenith']
         elif model in trues:
             zenith = solar_position['zenith']
-        else
+        else:
             raise ValueError('invalid model %s', model)
 
         airmass_relative = atmosphere.relativeairmass(zenith, model)
