class_docstr: BenchmarkRunner is responsible for benchmarking all the registered
  benchmark test groups.
  
  Attributes:
      tag_filter (str): control the benchmarks which matches the tag.
      operator (str): only run benchmark test cases that contains
  this filter string in the test case's id.
      test_name (str): only run benchmark test cases that matches this filter,
      this is a case-sensitive substring match and it happens in
      the _keep_test method.
class_docstr_tok: ["BenchmarkRunner","is","responsible","for","benchmarking","all","the","registered","benchmark","test","groups",".","Attributes",":","tag_filter","(","str",")",":","control","the","benchmarks","which","matches","the","tag",".","operator","(","str",")",":","only","run","benchmark","test","cases","that","contains","this","filter","string","in","the","test","case","'s","id",".","test_name","(","str",")",":","only","run","benchmark","test","cases","that","matches","this","filter",",","this","is","a","case-sensitive","substring","match","and","it","happens","in","the","_keep_test","method","."]
docstr: Use Python's timeit module to measure execution time (unit: second).
docstr_tok: ["Use","Python","'s","timeit","module","to","measure","execution","time","(","unit",":","second",")","."]
code: def _launch_forward(self, test_case, iters, print_per_iter):
      """Use Python's timeit module to measure execution time (unit: second)."""
      cuda_sync = "cuda" in test_case.test_config.test_name
      func = test_case.run_forward
      if self.use_jit:
          func = test_case.run_jit_forward
      forward_time = timeit.timeit(
          functools.partial(func, iters, print_per_iter, cuda_sync),
          number=1,
      )
      return forward_time
  
imports: import ast
  import copy
  import functools
  import json
  import timeit
  from collections import namedtuple
  import benchmark_utils
  import numpy
  import torch
  import torch.utils.cpp_extension
label_desc: Use image node_id 6 for calling the BenchmarkRunner obj's underlying member method code with example usage: obj._launch_forward(test_case, iters, print_per_iter) and returns: forward_time