diff --git a/pyproject.toml b/pyproject.toml
index efdb8ddd..c3b132f4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.black]
 line-length = 88
-py36 = true
+target-version = ['py36']
 include = '\.pyi?$'
 exclude = '''
 /(