Use explicit imports.

tools/SourceKit/bindings/python/sourcekitd/capi.py

@@ -10,7 +10,22 @@
 #
 #===------------------------------------------------------------------------===#
 
-from ctypes import *
+from ctypes import (
+    CFUNCTYPE,
+    POINTER,
+    Structure,
+    addressof,
+    c_bool,
+    c_char_p,
+    c_int,
+    c_int64,
+    c_size_t,
+    c_uint64,
+    c_void_p,
+    cdll,
+    py_object,
+    string_at,
+)
 
 # ctypes doesn't implicitly convert c_void_p to the appropriate wrapper
 # object. This is a problem, because it means that from_parameter will see an