diff --git a/.style.yapf b/.style.yapf
new file mode 100644
index 0000000..3bd5017
--- /dev/null
+++ b/.style.yapf
@@ -0,0 +1,4 @@
+[style]
+COLUMN_LIMIT = 119
+INDENT_WIDTH = 4
+USE_TABS = False
diff --git a/hello_world.py b/hello_world.py
index 1464990..9001f3e 100644
--- a/hello_world.py
+++ b/hello_world.py
@@ -1,8 +1,15 @@
+def vector(dim):
+    import numpy as np
+
+
+    return np.random.rand(dim)
+
 def message():
     return 'Hello, Danger world!'
 
 def main():
     print(message())
+    print(vector(10))
 
 if __name__ == '__main__':
     main()
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..612ba38
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,2 @@
+yapf
+futures