Reformat the source code using black

Change-Id: I54e7f6b9a60e4caa42158bf6259c671bc800e4a8
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..aa4949a
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,2 @@
+[tool.black]
+line-length = 100