diff --git a/twine/package.py b/twine/package.py
index e5d424c8..745752ff 100644
--- a/twine/package.py
+++ b/twine/package.py
@@ -48,6 +48,9 @@ def _safe_name(name: str) -> str:
     """Convert an arbitrary string to a standard distribution name.
 
     Any runs of non-alphanumeric/. characters are replaced with a single '-'.
+
+    Copied from pkg_resources.safe_name for compatibility with warehouse.
+    See https://github.com/pypa/twine/issues/743.
     """
     return re.sub("[^A-Za-z0-9.]+", "-", name)