gnu: Add python-aiostream.

* gnu/packages/python-web.scm (python-aiostream): New variable.

gnu/packages/python-web.scm

@@ -513,6 +513,35 @@ (define-public python-aiorpcx-0.18
         (base32
          "1rswrspv27x33xa5bnhrkjqzhv0sknv5kd7pl1vidw9d2z4rx2l0"))))))
 
+(define-public python-aiostream
+  (package
+    (name "python-aiostream")
+    (version "0.4.5")
+    (source (origin
+              ;; Tests not included in pypi release.
+              (method git-fetch)
+              (uri (git-reference
+                    (url "https://github.com/vxgmichel/aiostream")
+                    (commit (string-append "v" version))))
+              (file-name (git-file-name name version))
+              (sha256
+               (base32
+                "0l2ijb7yk0820wiyf6zrzx8fhzf8925an7r06mcaw3in1mr6rssq"))))
+    (build-system python-build-system)
+    (native-inputs
+     (list python-pytest
+           python-pytest-asyncio
+           python-pytest-cov
+           python-pytest-runner))
+    (home-page "https://github.com/vxgmichel/aiostream")
+    (synopsis "Generator-based operators for asynchronous iteration")
+    (description "@code{aiostream} provides a collection of stream operators that can
+be combined to create asynchronous pipelines of operations.  It can be seen as an
+asynchronous version of @code{itertools}, although some aspects are slightly
+different. All the provided operators return a unified interface called a stream.  A
+stream is an enhanced asynchronous iterable.")
+    (license license:gpl3)))
+
 (define-public python-asgiref
   (package
     (name "python-asgiref")