def install(self, install_options, global_options=(), *args, **kwargs):
        to_install = [r for r in self.requirements.values()
                      if not r.satisfied_by]

        if to_install:
            logger.notify('Installing collected packages: %s' % ', '.join([req.name for req in to_install]))
        logger.indent += 2
        try:
            for requirement in to_install:
                if requirement.conflicts_with:
                    logger.notify('Found existing installation: %s'
                                  % requirement.conflicts_with)
                    logger.indent += 2
                    try:
                        requirement.uninstall(auto_confirm=True)
                    finally:
                        logger.indent -= 2
                try:
                    requirement.install(install_options, global_options, *args, **kwargs)
                except:
                    # if install did not succeed, rollback previous uninstall
                    if requirement.conflicts_with and not requirement.install_succeeded:
                        requirement.rollback_uninstall()
                    raise
                else:
                    if requirement.conflicts_with and requirement.install_succeeded:
                        requirement.commit_uninstall()
                requirement.remove_temporary_source()
        finally:
            logger.indent -= 2
        self.successfully_installed = to_install
Install everything in this set (after having downloaded and unpacked the packages)
dataset/ETHPy150Open balanced/status.balancedpayments.com/venv/lib/python2.7/site-packages/pip-1.3.1-py2.7.egg/pip/req.py/RequirementSet.install