code: def _legacy_fetch_build_egg(dist, req):
      """Fetch an egg needed for building.
  
      Legacy path using EasyInstall.
      """
      tmp_dist = dist.__class__({"script_args": ["easy_install"]})
      opts = tmp_dist.get_option_dict("easy_install")
      opts.clear()
      opts.update(
          (k, v)
          for k, v in dist.get_option_dict("easy_install").items()
          if k
          in (
              # don't use any other settings
              "find_links",
              "site_dirs",
              "index_url",
              "optimize",
              "site_dirs",
              "allow_hosts",
          )
      )
      if dist.dependency_links:
          links = dist.dependency_links[:]
          if "find_links" in opts:
              links = _fixup_find_links(opts["find_links"][1]) + links
          opts["find_links"] = ("setup", links)
      install_dir = dist.get_egg_cache_dir()
      cmd = easy_install(
          tmp_dist,
          args=["x"],
          install_dir=install_dir,
          exclude_scripts=True,
          always_copy=False,
          build_directory=None,
          editable=False,
          upgrade=False,
          multi_version=True,
          no_report=True,
          user=False,
      )
      cmd.ensure_finalized()
      return cmd.easy_install(req)
  
file_path: catboost/contrib/python/setuptools/py2/setuptools/installer.py
imports: import glob
  import os
  import subprocess
  import sys
  from distutils import log
  from distutils.errors import DistutilsError
  import pkg_resources
  from setuptools.command.easy_install import easy_install
  from setuptools.extern import six
  from setuptools.wheel import Wheel
  from .py31compat import TemporaryDirectory
label_desc: Use image node_id 2 for calling a global function with example usage: _legacy_fetch_build_egg(dist, req) and returns: cmd