code: def _project_is_apache():
      
  
      global _is_apache_cache
      if _is_apache_cache is not None:
          return _is_apache_cache
      license_files = ["LICENSE"]
      for filename in license_files:
          try:
              with open(filename, "r") as file:
                  for line in file:
                      if re.search('Apache License', line):
                          _is_apache_cache = True
                          return True
          except IOError:
              pass
      _is_apache_cache = False
      return False
docs: Determine if a project is Apache.
  
      Look for a key string in a set of possible license files to figure out
      if a project looks to be Apache. This is used as a precondition for
      enforcing license headers.