code: def prepare_pip_requirements_file_if_needed(requirements):
      
      if utility.any_contains_any(requirements, "<>|()&^"):
          file_path, janitor = pip_requirements_file(requirements)
          requirements[:] = ["-r", file_path]
          return janitor
docs: Make requirements be passed to pip via a requirements file if needed.
  
      We must be careful about how we pass shell operator characters (e.g. '<',
      '>', '|' or '^') included in our command-line arguments or they might cause
      problems if run through an intermediate shell interpreter. If our pip
      requirement specifications contain such characters, we pass them using a
      separate requirements file.
  
      This problem has been encountered on Windows 7 SP1 x64 using Python 2.4.3,
      2.4.4 & 2.5.4.