diff --git a/build.sh b/build.sh
index d99c3c9..705b65e 100755
--- a/build.sh
+++ b/build.sh
@@ -5,5 +5,6 @@
 set -euf
 bash style.sh
 bash tests.sh
+rm -rf build
 rm -rf dist
 python3 setup.py sdist bdist_wheel
diff --git a/exabel_data_sdk/stubs/__init__.py b/exabel_data_sdk/stubs/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/__init__.py b/exabel_data_sdk/stubs/exabel/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/api/__init__.py b/exabel_data_sdk/stubs/exabel/api/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/api/data/__init__.py b/exabel_data_sdk/stubs/exabel/api/data/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/api/data/v1/__init__.py b/exabel_data_sdk/stubs/exabel/api/data/v1/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/api/math/__init__.py b/exabel_data_sdk/stubs/exabel/api/math/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/exabel/api/time/__init__.py b/exabel_data_sdk/stubs/exabel/api/time/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/google/__init__.py b/exabel_data_sdk/stubs/google/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/exabel_data_sdk/stubs/google/api/__init__.py b/exabel_data_sdk/stubs/google/api/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/setup.py b/setup.py
index f5e4022..99e10c2 100644
--- a/setup.py
+++ b/setup.py
@@ -5,7 +5,7 @@
 
 setuptools.setup(
     name="exabel-data-sdk",
-    version="0.0.19",
+    version="0.0.20",
     author="Exabel",
     author_email="support@exabel.com",
     description="Python SDK for the Exabel Data API",