code: def createSharedLibBuilder(env):
      
  
      try:
          shared_lib = env['BUILDERS']['SharedLibrary']
      except KeyError:
          import SCons.Defaults
          action_list = [ SCons.Defaults.SharedCheck,
                          SCons.Defaults.ShLinkAction,
                          LibSymlinksAction ]
          shared_lib = SCons.Builder.Builder(action = action_list,
                                             emitter = "$SHLIBEMITTER",
                                             prefix = ShLibPrefixGenerator,
                                             suffix = ShLibSuffixGenerator,
                                             target_scanner = ProgramScanner,
                                             src_suffix = '$SHOBJSUFFIX',
                                             src_builder = 'SharedObject')
          env['BUILDERS']['SharedLibrary'] = shared_lib
  
      return shared_lib
docs: This is a utility function that creates the SharedLibrary
      Builder in an Environment if it is not there already.
  
      If it is already there, we return the existing one.