Don't require stdlib backports for Python 3.8+

no-backports.patch

@@ -0,0 +1,24 @@
+commit 187fedd9e1d91ee835b60d6c21a31c85f2eda719
+Author: Petr Viktorin <encukou@gmail.com>
+Date:   Wed Nov 13 14:35:24 2019 +0100
+
+    Don't pull in importlib_metadata & zipp backports for Python 3.8+
+    
+    The Python 3.8+ standard library importlib.metadata and zipfile.Path
+    are preferred over the backports.
+
+diff --git a/pyproject.toml b/pyproject.toml
+index 7c6e1d2..cb2dc76 100644
+--- a/pyproject.toml
++++ b/pyproject.toml
+@@ -10,8 +10,8 @@ home-page = "https://github.com/pypa/pep517"
+ description-file = "README.rst"
+ requires = [
+     "toml",
+-    "importlib_metadata",
+-    "zipp",
++    "importlib_metadata;python_version<'3.8'",
++    "zipp;python_version<'3.8'",
+ ]
+ classifiers = ["License :: OSI Approved :: MIT License"]
+ 

python-pep517.spec

@@ -13,6 +13,10 @@ URL:            https://github.com/takluyver/pep517
 Source0:        %{pypi_source}
 BuildArch:      noarch
 
+# Don't require stdlib backport modules on Python 3.8+
+# Submitted upstream: https://github.com/pypa/pep517/pull/70
+Patch0:         no-backports.patch
+
 # Don't use %%pyproject_buildrequires to avoid a build dependency loop.
 BuildRequires:  python3-devel
 BuildRequires:  pyproject-rpm-macros