How to use the py2app.build_app.Target function in py2app

try:
        targets = eval(targets)
    except:
        pass
    ret = []
    for target_def in targets:
        if isinstance(target_def, basestring):
            # Create a default target object, with the string as the attribute
            target = Target(**{default_attribute: target_def})
        else:
            d = getattr(target_def, "__dict__", target_def)
            if default_attribute not in d:
                raise DistutilsOptionError(
                    "This target class requires an attribute '%s'"
                    % (default_attribute,))
            target = Target(**d)
        target.validate()
        ret.append(target)
    return ret

def _make_py2app_cmd(dist_dir,distribution,options,exes):
    exe = exes[0]
    extra_exes = exes[1:]
    cmd = py2app(distribution)
    for (nm,val) in options.iteritems():
        setattr(cmd,nm,val)
    cmd.dist_dir = dist_dir
    cmd.app = [Target(script=exe.script,dest_base=exe.name)]
    cmd.extra_scripts = [e.script for e in extra_exes]
    cmd.finalize_options()
    cmd.plist["CFBundleExecutable"] = exe.name
    old_run = cmd.run
    def new_run():
        #  py2app munges the environment in ways that break things.
        old_deployment_target = os.environ.get("MACOSX_DEPLOYMENT_TARGET",None)
        old_run()
        if old_deployment_target is None:
            os.environ.pop("MACOSX_DEPLOYMENT_TARGET",None)
        else:
            os.environ["MACOSX_DEPLOYMENT_TARGET"] = old_deployment_target
        #  We need to script file to have the same name as the exe, which
        #  it won't if they have changed it explicitly.
        resdir = os.path.join(dist_dir,distribution.get_name()+".app","Contents/Resources")
        scriptf = os.path.join(resdir,exe.name+".py")

def FixupTargets(targets, default_attribute):
    if not targets:
        return targets
    try:
        targets = eval(targets)
    except:
        pass
    ret = []
    for target_def in targets:
        if isinstance(target_def, basestring):
            # Create a default target object, with the string as the attribute
            target = Target(**{default_attribute: target_def})
        else:
            d = getattr(target_def, "__dict__", target_def)
            if default_attribute not in d:
                raise DistutilsOptionError(
                    "This target class requires an attribute '%s'"
                    % (default_attribute,))
            target = Target(**d)
        target.validate()
        ret.append(target)
    return ret