未定义名称“cc\u library”

tools/vector_gen.bzl

def drake_cc_vector_gen_library(
        name,    
        srcs = [],
        deps = [],
        **kwargs):
    generated = cc_vector_gen(
        name = name + "_codegen",
        srcs = srcs,
        include_prefix = "drake",
        drake_workspace_name = "",
        visibility = [],
    )
    cc_library(
        name = name,
        srcs = generated.srcs,
        hdrs = generated.hdrs,
        deps = deps + generated.deps,
        **kwargs
    )

project/BUILD.bazel

load("//tools:vector_gen.bzl", "cc_vector_gen_library")

cc_vector_gen_library(
    name = "x",
    srcs = [
      "x.yaml",
    ],
    visibility = ["//visibility:public"],
)

但是当我尝试 bazel build //... 在目录的顶端

ERROR: /root/doublependulum/tools/vector_gen.bzl:170:5: name 'cc_library' is not defined
ERROR: Skipping '.': error loading package 'double_pendulum': Extension 'tools/vector_gen.bzl' has errors
WARNING: Target pattern parsing failed.
ERROR: Extension 'tools/vector_gen.bzl' has errors

我想我不明白。不是吗 cc_library 总是被定义?否则怎么导入?