Add permission check before configuration10

Author: JasonMo1

src/pip/_internal/configuration.py

@@ -211,12 +211,12 @@ def save(self) -> None:
             ensure_dir(os.path.dirname(fname))
 
             # Ensure directory's permission(need to be writeable)
-            if os.access(fname, os.W_OK):
+            try:
                 with open(fname, "w") as f:
                     parser.write(f)
-            else:
+            except IOError as error:
                 raise ConfigurationError(
-                "Configuation file not writeable {}".format(': '.join(fname))
+                "An error occurred while writing to the configuration file: {0}\nError message: {1}".format(fname, error)
                 )
 
     #
@@ -342,24 +342,10 @@ def iter_config_files(self) -> Iterable[Tuple[Kind, List[str]]]:
         # at the base we have any global configuration
         yield kinds.GLOBAL, config_files[kinds.GLOBAL]
 
-        site_accessable = int
-        site_index = 0
-        site_all_accessable = bool
-
-        for fname in config_files[kinds.SITE]:
-            site_index += 1
-            if os.access(fname, os.W_OK):
-                site_accessable += 1
-
-        if site_accessable < site_index:
-            site_all_accessable = False
-        elif site_accessable == site_index:
-            site_all_accessable = True
-        
         # per-user configuration next
         should_load_user_config = not self.isolated and not (
             config_file and os.path.exists(config_file)
-        ) or not site_all_accessable == True
+        ) 
 
         if should_load_user_config:
             # The legacy config file is overridden by the new config file