gnu: Add python-spake2.

* gnu/packages/python-crypto.scm (python-spake2): New variable.

gnu/packages/python-crypto.scm

@@ -1016,3 +1016,23 @@ relevant RFCs too.")
     (description "This package provides a Python implementation of the HMAC Key
 Derivation function (HKDF) defined in RFC 5869.")
     (license license:bsd-2)))
+
+(define-public python-spake2
+  (package
+    (name "python-spake2")
+    (version "0.8")
+    (source
+      (origin
+        (method url-fetch)
+        (uri (pypi-uri "spake2" version))
+        (sha256
+         (base32
+          "1x16r7lrbklvfzbacb66qv9iiih6liq1y612dqh2chgf555n2yn1"))))
+    (build-system python-build-system)
+    (propagated-inputs
+     `(("python-hkdf" ,python-hkdf)))
+    (home-page "https://github.com/warner/python-spake2")
+    (synopsis "SPAKE2 password-authenticated key exchange in Python")
+    (description "This package provides a Python implementation of the SPAKE2
+Password-Authenticated Key Exchange algorithm.")
+    (license license:expat)))