update zipimporter of activate_zipapps.py

Author: ClericPy

README.md

@@ -78,7 +78,7 @@ So, what could `zipapps` be?
 ## 4. Activate the `.pyz` environment
 
 1. use `zipimport` (Recommended)
-   1. `sys.path.append("some_lib_venv.pyz");importlib.import_module("ensure_zipapps")`
+   1. `sys.path.insert(0, "some_lib_venv.pyz");importlib.import_module("ensure_zipapps")`
    2. automatically unzip cache, and add the path to sys.path
       1. it can be run multiple times
 2. if they are all pure-python code and **no need to decompress**

zipapps/activate_zipapps.py

@@ -1,4 +1,3 @@
-import zipimport
 import sys
 import zipfile
 from pathlib import Path
@@ -9,14 +8,19 @@ def activate(path=None):
     path_str = path.absolute().as_posix()
     if zipfile.is_zipfile(path_str):
         try:
-            importer = zipimport.zipimporter(path_str)
-            spec = importer.find_spec("ensure_zipapps")
-            if spec and spec.loader is not None:
-                ensure_zipapps = spec.loader.load_module("ensure_zipapps")
-                del ensure_zipapps
-                sys.modules.pop("ensure_zipapps", None)
-            else:
-                raise ImportError(f"Cannot find 'ensure_zipapps' in {path_str!r}")
+            from zipimport import zipimporter
+
+            importer = zipimporter(path_str)
+            try:
+                spec = importer.find_spec("ensure_zipapps")  # 返回ModuleSpec
+                if spec and spec.loader:
+                    module = spec.loader.load_module("ensure_zipapps")  # 直接加载
+                else:
+                    raise ImportError("Module not found")
+            except AttributeError:
+                module = importer.load_module("ensure_zipapps")
+            del module
+            sys.modules.pop("ensure_zipapps", None)
         except ImportError as err:
             sys.stderr.write(f"WARNING: activate failed for {err!r}\n")
             raise err