Better time output on build completion.

var/spack/packages/py-pyqt/package.py

@@ -1,18 +1,21 @@
 from spack import *
 
-class PyPyqt4(Package):
-    """PyQt is a set of Python v2 and v3 bindings for Digia's Qt application framework and runs on all platforms supported by Qt including Windows, MacOS/X and Linux."""
+class PyPyqt(Package):
+    """PyQt is a set of Python v2 and v3 bindings for Digia's Qt
+       application framework and runs on all platforms supported by Qt
+       including Windows, MacOS/X and Linux."""
     homepage = "http://www.riverbankcomputing.com/software/pyqt/intro"
     url      = "http://sourceforge.net/projects/pyqt/files/PyQt4/PyQt-4.11.3/PyQt-x11-gpl-4.11.3.tar.gz"
 
     version('4.11.3', '997c3e443165a89a559e0d96b061bf70')
 
     extends('python')
-    depends_on('qt')
+    depends_on('qt@4')  # TODO: allow qt5 when conditional deps are supported.
     depends_on('py-sip')
 
     def install(self, spec, prefix):
-        version_array = str(spec['python'].version).split('.')
-        python('configure.py', '--confirm-license', '--destdir=%s/python%s.%s/site-packages' %(self.prefix.lib, version_array[0], version_array[1]))
+        python('configure.py',
+               '--confirm-license',
+               '--destdir=%s' % site_packages_dir)
         make()
         make('install')