old_contents: import logging
  
  from pip._internal.utils.logging import indent_log
  from pip._internal.utils.setuptools_build import make_setuptools_develop_args
  from pip._internal.utils.subprocess import call_subprocess
  from pip._internal.utils.typing import MYPY_CHECK_RUNNING
  
  if MYPY_CHECK_RUNNING:
      from typing import List, Optional, Sequence
  
      from pip._internal.build_env import BuildEnvironment
  
  
  logger = logging.getLogger(__name__)
  
  
  def install(
      install_options,  # type: List[str]
      global_options,  # type: Sequence[str]
      prefix,  # type: Optional[str]
      home,  # type: Optional[str]
      use_user_site,  # type: bool
      name,  # type: str
      setup_py_path,  # type: str
      isolated,  # type: bool
      build_env,  # type: BuildEnvironment
      unpacked_source_directory,  # type: str
  ):
      # type: (...) -> None
      logger.info('Running setup.py develop for %s', name)
  
      args = make_setuptools_develop_args(
          setup_py_path,
          global_options=global_options,
          install_options=install_options,
          no_user_config=isolated,
          prefix=prefix,
          home=home,
          use_user_site=use_user_site,
      )
  
      with indent_log():
          with build_env:
              call_subprocess(
                  args,
                  cwd=unpacked_source_directory,
              )
  
new_contents: """Legacy installation process, i.e. `setup.py develop`.
  """
  import logging
  
  from pip._internal.utils.logging import indent_log
  from pip._internal.utils.setuptools_build import make_setuptools_develop_args
  from pip._internal.utils.subprocess import call_subprocess
  from pip._internal.utils.typing import MYPY_CHECK_RUNNING
  
  if MYPY_CHECK_RUNNING:
      from typing import List, Optional, Sequence
  
      from pip._internal.build_env import BuildEnvironment
  
  
  logger = logging.getLogger(__name__)
  
  
  def install(
      install_options,  # type: List[str]
      global_options,  # type: Sequence[str]
      prefix,  # type: Optional[str]
      home,  # type: Optional[str]
      use_user_site,  # type: bool
      name,  # type: str
      setup_py_path,  # type: str
      isolated,  # type: bool
      build_env,  # type: BuildEnvironment
      unpacked_source_directory,  # type: str
  ):
      # type: (...) -> None
      """Install a package in editable mode. Most arguments are pass-through
      to setuptools.
      """
      logger.info('Running setup.py develop for %s', name)
  
      args = make_setuptools_develop_args(
          setup_py_path,
          global_options=global_options,
          install_options=install_options,
          no_user_config=isolated,
          prefix=prefix,
          home=home,
          use_user_site=use_user_site,
      )
  
      with indent_log():
          with build_env:
              call_subprocess(
                  args,
                  cwd=unpacked_source_directory,
              )
  
subject: Add docstrings