diff -Nru dput-1.0.3ubuntu1/debian/changelog dput-1.0.3ubuntu1.1/debian/changelog
--- dput-1.0.3ubuntu1/debian/changelog	2019-04-22 12:31:01.000000000 +0200
+++ dput-1.0.3ubuntu1.1/debian/changelog	2023-06-29 16:58:12.000000000 +0200
@@ -1,3 +1,9 @@
+dput (1.0.3ubuntu1.1) focal; urgency=medium
+
+  * Make versions with Ubuntu suffixes compliant with PEP 440 (LP: #1991606)
+
+ -- Benjamin Drung <bdrung@ubuntu.com>  Thu, 29 Jun 2023 16:58:12 +0200
+
 dput (1.0.3ubuntu1) eoan; urgency=medium
 
   [ Julian Andres Klode ]
diff -Nru dput-1.0.3ubuntu1/setup.py dput-1.0.3ubuntu1.1/setup.py
--- dput-1.0.3ubuntu1/setup.py	2019-04-22 12:31:01.000000000 +0200
+++ dput-1.0.3ubuntu1.1/setup.py	2023-06-29 16:58:04.000000000 +0200
@@ -11,6 +11,7 @@
 import os
 import os.path
 import pydoc
+import re
 import unittest
 
 import debian.changelog
@@ -21,6 +22,22 @@
         setup,
         )
 
+
+def make_pep440_compliant(version: str) -> str:
+    """Convert the version into a PEP440 compliant version."""
+    public_version_re = re.compile(
+        r"^([0-9][0-9.]*(?:(?:a|b|rc|.post|.dev)[0-9]+)*)\+?"
+    )
+    _, public, local = public_version_re.split(version, maxsplit=1)
+    if not local:
+        return version
+    sanitized_local = re.sub("[+~]+", ".", local).strip(".")
+    pep440_version = f"{public}+{sanitized_local}"
+    assert re.match(
+        "^[a-zA-Z0-9.]+$", sanitized_local
+    ), f"'{pep440_version}' not PEP440 compliant"
+    return pep440_version
+
 
 setup_dir = os.path.dirname(__file__)
 
@@ -55,7 +72,7 @@
 
 setup_kwargs = dict(
         name=changelog.package,
-        version=str(changelog.version),
+        version=make_pep440_compliant(str(changelog.version)),
         packages=find_packages(exclude=["test"]),
 
         # Setuptools metadata.