Add back missing dependencies after spack#33898

var/spack/repos/builtin/packages/py-black/package.py

@@ -52,6 +52,9 @@ class PyBlack(PythonPackage):
     depends_on("[email protected]:", when="+jupyter", type=("build", "run"))
     depends_on("[email protected]:", when="+jupyter", type=("build", "run"))
 
+    # Needed because this package is used to bootstrap Spack (Spack supports Python 3.6+)
+    depends_on("[email protected]:", when="^python@:3.6", type=("build", "run"))
+
     # see: https://github.com/psf/black/issues/2964
     # note that pip doesn't know this constraint.
     depends_on("py-click@:8.0", when="@:22.2", type=("build", "run"))

var/spack/repos/builtin/packages/py-dataclasses/package.py

@@ -0,0 +1,19 @@
+# Copyright 2013-2022 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack.package import *
+
+
+class PyDataclasses(PythonPackage):
+    """A backport of the dataclasses module for Python 3.6"""
+
+    homepage = "https://github.com/ericvsmith/dataclasses"
+    pypi = "dataclasses/dataclasses-0.7.tar.gz"
+
+    version("0.8", sha256="8479067f342acf957dc82ec415d355ab5edb7e7646b90dc6e2fd1d96ad084c97")
+    version("0.7", sha256="494a6dcae3b8bcf80848eea2ef64c0cc5cd307ffc263e17cdf42f3e5420808e6")
+
+    depends_on("[email protected]:3.6", type=("build", "run"))
+    depends_on("py-setuptools", type="build")

var/spack/repos/builtin/packages/python/package.py

@@ -107,6 +107,13 @@ class Python(Package):
     version("3.7.1", sha256="36c1b81ac29d0f8341f727ef40864d99d8206897be96be73dc34d4739c9c9f06")
     version("3.7.0", sha256="85bb9feb6863e04fb1700b018d9d42d1caac178559ffa453d7e6a436e259fd0d")
 
+    # Python 3.6.15 has been added back only to allow bootstrapping Spack on Python 3.6
+    version(
+        "3.6.15",
+        sha256="54570b7e339e2cfd72b29c7e2fdb47c0b7b18b7412e61de5b463fc087c13b043",
+        deprecated=True,
+    )
+
     extendable = True
 
     # Variants to avoid cyclical dependencies for concretizer