diff --git a/var/spack/repos/builtin/packages/python/package.py b/var/spack/repos/builtin/packages/python/package.py
index 4a91dab438..07097899ee 100644
--- a/var/spack/repos/builtin/packages/python/package.py
+++ b/var/spack/repos/builtin/packages/python/package.py
@@ -37,7 +37,7 @@ class Python(AutotoolsPackage):
     version('3.8.2',  sha256='e634a7a74776c2b89516b2e013dda1728c89c8149b9863b8cea21946daf9d561')
     version('3.8.1',  sha256='c7cfa39a43b994621b245e029769e9126caa2a93571cee2e743b213cceac35fb')
     version('3.8.0',  sha256='f1069ad3cae8e7ec467aa98a6565a62a48ef196cb8f1455a245a08db5e1792df')
-    version('3.7.8',  sha256='0e25835614dc221e3ecea5831b38fa90788b5389b99b675a751414c858789ab0', preferred=True)
+    version('3.7.8',  sha256='0e25835614dc221e3ecea5831b38fa90788b5389b99b675a751414c858789ab0')
     version('3.7.7',  sha256='8c8be91cd2648a1a0c251f04ea0bb4c2a5570feb9c45eaaa2241c785585b475a')
     version('3.7.6',  sha256='aeee681c235ad336af116f08ab6563361a0c81c537072c1b309d6e4050aa2114')
     version('3.7.5',  sha256='8ecc681ea0600bbfb366f2b173f727b205bb825d93d2f0b286bc4e58d37693da')