How to use the pkgconfig.run_pkg_config function in pkgconfig

def CheckLua(context, require_version):
    env = context.env
    backup = env.Clone().Dictionary()

    context.Message("Checking for Lua development files version " + require_version + "... ")

    version = ".".join(require_version.split(".")[0:2])

    if env.get("luadir"):
        env.Append(LIBPATH = ["$luadir"], CPPPATH = ["$luadir/include"], LIBS = "lua" + version)
        found = True
    else:
        found = run_pkg_config(context, "lua >= " + require_version) or run_pkg_config(context, "lua" + version + " >= " + require_version) or run_pkg_config(context, "lua-" + version + " >= " + require_version)
        if not found:
            try:
                prefix, include = find_include([env["prefix"]], "lualib.h", default_prefixes=not env["host"])[0]
                found = True
                context.Log("Found Lua header " + include + ".\n")
                env.Append(LIBPATH = [join(prefix, "lib")], CPPPATH = [join(prefix, "include")], LIBS = ["lua"])
            except IndexError:
                pass

    result = found and context.TryLink("""
    #include 
    #include 
    int main() { luaL_newstate(); }
    """, ".c")
    if result:
        context.Result("yes")

def CheckQtPkg(context, env, name, qtdir):
    str=" "
    seq=("Checking for", name, "development files... ")
    context.Message(str.join(seq))

    if qtdir:
        backup_pkg_config_path = env["ENV"]["PKG_CONFIG_PATH"]
        env["ENV"]["PKG_CONFIG_PATH"] = AppendPath(env.get("PKG_CONFIG_PATH",""), join(qtdir, "lib/pkgconfig"), sep=',')

    found = run_pkg_config(context, name)

    if qtdir:
        env["ENV"]["PKG_CONFIG_PATH"] = backup_pkg_config_path

    if found:
        context.Result("yes")
        return True
    else:
        context.Result("no")
        return False