diff --git a/third_party/astor.BUILD b/third_party/astor.BUILD
index c244e47ab7045f..58fe9acf3326fb 100644
--- a/third_party/astor.BUILD
+++ b/third_party/astor.BUILD
@@ -19,5 +19,6 @@ py_library(
         "astor/string_repr.py",
         "astor/tree_walk.py",
     ],
+    srcs_version = "PY2AND3",
     visibility = ["//visibility:public"],
 )
diff --git a/third_party/gast.BUILD b/third_party/gast.BUILD
index 0ccf8eff58ef38..06db528ada27e2 100644
--- a/third_party/gast.BUILD
+++ b/third_party/gast.BUILD
@@ -14,5 +14,6 @@ py_library(
         "gast/astn.py",
         "gast/gast.py",
     ],
+    srcs_version = "PY2AND3",
     visibility = ["//visibility:public"],
 )
diff --git a/third_party/termcolor.BUILD b/third_party/termcolor.BUILD
index 94fcb3beaaf471..6000e3289deff8 100644
--- a/third_party/termcolor.BUILD
+++ b/third_party/termcolor.BUILD
@@ -10,5 +10,6 @@ py_library(
     srcs = [
         "termcolor.py",
     ],
+    srcs_version = "PY2AND3",
     visibility = ["//visibility:public"],
 )