尽可能修补 Gen 的导入

App/lib/core/Gen/AssignGenMixin.vp

@@ -21,6 +21,8 @@ import lib.core.Gen.CallGenBase as CallGenBase
 import lib.core.Gen.CallGenFd as CallGenFd
 import lib.core.Gen.CallGenVt as CallGenVt
 
+import lib.Stub.StubGen.VpiReader as VpiReader
+
 # ============================================================
 # AssignGenMixin - 赋值翻译 Mixin（P6 方法化）
 #
@@ -2045,7 +2047,6 @@ class AssignGenMixin:
                             mod_sha1_rhs: str = self.Gen.CallGenBase._lookup_module_sha1(
                                 mod_nm_rhs.id)
                             if mod_sha1_rhs is not None:
-                                import lib.StubGen.VpiReader as VpiReader
                                 temp_dir_rhs: str = None
                                 if self.Gen.CallGenBase.TempDir is not None:
                                     temp_dir_rhs = self.Gen.CallGenBase.TempDir
@@ -2068,7 +2069,6 @@ class AssignGenMixin:
                     cls_sha1 = trans.ModuleSha1
                 ret_cls: str = None
                 if cls_sha1 is not None:
-                    import lib.StubGen.VpiReader as VpiReader
                     temp_dir: str = None
                     if self.Gen.CallGenBase.TempDir is not None:
                         temp_dir = self.Gen.CallGenBase.TempDir