Drop handling for missing _copy_from().

Author: barneygale

Lib/pathlib/__init__.py

@@ -1105,11 +1105,7 @@ def copy(self, target, **kwargs):
         if not hasattr(target, 'with_segments'):
             target = self.with_segments(target)
         ensure_distinct_paths(self, target)
-        try:
-            copy_to_target = target._copy_from
-        except AttributeError:
-            raise TypeError(f"Target path is not writable: {target!r}") from None
-        copy_to_target(self, **kwargs)
+        target._copy_from(self, **kwargs)
         return target.joinpath()  # Empty join to ensure fresh metadata.
 
     def copy_into(self, target_dir, **kwargs):

Lib/pathlib/types.py

@@ -331,11 +331,7 @@ def copy(self, target, **kwargs):
         Recursively copy this file or directory tree to the given destination.
         """
         ensure_distinct_paths(self, target)
-        try:
-            copy_to_target = target._copy_from
-        except AttributeError:
-            raise TypeError(f"Target path is not writable: {target!r}") from None
-        copy_to_target(self, **kwargs)
+        target._copy_from(self, **kwargs)
         return target.joinpath()  # Empty join to ensure fresh metadata.
 
     def copy_into(self, target_dir, **kwargs):