exclude lxml 4.7 because the wheels are missing the lxml includes

graingert · hoefling · commit cf38b52c81d8 · 2021-12-13T12:50:39.000+01:00
see https://bugs.launchpad.net/lxml/+bug/1954644
diff --git a/pyproject.toml b/pyproject.toml
@@ -23,4 +23,4 @@ known_first_party = ['xmlsec']
 known_third_party = ['lxml', 'pytest', '_pytest', 'hypothesis']
 
 [build-system]
-requires = ['setuptools>=42', 'wheel', 'setuptools_scm[toml]>=3.4']
+requires = ['setuptools>=42', 'wheel', 'setuptools_scm[toml]>=3.4', "pkgconfig>=1.5.1", "lxml>=3.8, !=4.7.0"]
diff --git a/requirements.txt b/requirements.txt
@@ -1,2 +1,2 @@
 pkgconfig
-lxml >= 3.8.0
+lxml >= 3.8.0, !=4.7.0
