diff --git a/CI/test_coverage.py b/CI/test_coverage.py
index 1f2dc560e8c..0488a71d85d 100755
--- a/CI/test_coverage.py
+++ b/CI/test_coverage.py
@@ -63,7 +63,7 @@ def call(cmd):
 if not os.path.exists(coverage_dir):
     os.makedirs(coverage_dir)
 
-excludes = ["-e", "../Tests/", "-e", ".*json.hpp"]
+excludes = ["-e", "../Tests/", "-e", r".*json\.hpp"]
 
 # create the html report
 call(