class_docstr: Test ability to marshall button protos.
docstr: Test use_container_width is false by default.
docstr_tok: ["Test","use_container_width","is","false","by","default","."]
code: def test_use_container_width_is_false_by_default(self):
      """Test use_container_width is false by default."""
      st.button("the label")
  
      c = self.get_delta_from_queue().new_element.button
      self.assertEqual(c.use_container_width, False)
  
file_path: streamlit/lib/tests/streamlit/elements/button_test.py
imports: import streamlit
  from tests.delta_generator_test_case import DeltaGeneratorTestCase
label_desc: Use image node_id 5 for calling the ButtonTest obj's underlying member method code with example usage: obj.test_use_container_width_is_false_by_default() without return types