def CheckInstalledLibrary(name, desired):
 dependencies = PACKAGES[name][1][desired]
 if dependencies:
  for (dep_name, dep_version) in dependencies:
   AllowInstalledLibrary(dep_name, dep_version)
 CheckInstalledVersion(name, desired, explicit=True)

def CheckInstalledLibrary ( name , desired ) : dependencies = PACKAGES [ name ] [ 1 ] [ desired ] if dependencies : for ( dep_name , dep_version ) in dependencies : AllowInstalledLibrary ( dep_name , dep_version ) CheckInstalledVersion ( name , desired , explicit = True )
check that the library and its dependencies are installed .