class_docstr: Example event timer to measure step and observation times.
class_docstr_tok: ["Example","event","timer","to","measure","step","and","observation","times","."]
code: def __enter__(self):
      pass
  
file_path: pysc2/pysc2/lib/metrics.py
label_desc: Use image node_id 1 for calling the _EventTimer obj's underlying member method code with example usage: obj.__enter__() without return types