calling pip as external process as it is the recommended way: https:/…

…/pip.pypa.io/en/stable/user_guide/#using-pip-from-your-program

src/wai/lazypip/_check.py

@@ -1,38 +1,11 @@
 from importlib import import_module
 from inspect import getmembers, isclass
-import logging
-import pip
+import subprocess
+import sys
 import traceback
 from ._venv import is_venv
 
 
-def backup_root_logger():
-    """
-    Creates a backup of the root logger.
-
-    :return: the backup
-    :rtype: dict
-    """
-    result = dict()
-    result['level'] = logging.root.level
-    result['disabled'] = logging.root.disabled
-    result['handlers'] = logging.root.handlers[:]
-    return result
-
-
-def restore_root_logger(backup):
-    """
-    Restores the root logger from the backup.
-
-    :param backup: the backup (level/disable/handlers)
-    :type backup: dict
-    """
-
-    logging.root.level = backup['level']
-    logging.root.disabled = backup['disabled']
-    logging.root.handlers = backup['handlers']
-
-
 def install_packages(packages, pip_args=None):
     """
     Installs the required packages.
@@ -43,23 +16,17 @@ def install_packages(packages, pip_args=None):
     :type pip_args: list
     """
 
-    # calling pip.main changes the root logger setup
-    backup = backup_root_logger()
-
     print("installing", packages)
     try:
-        args = ["install"]
+        cmd = [sys.executable, "-m", "pip", "install"]
         if not pip_args is None:
-            args.extend(pip_args)
-        args.extend(packages)
-        pip.main(args)
+            cmd.extend(pip_args)
+        cmd.extend(packages)
+        subprocess.check_call(cmd)
     except:
         print("Failed to install: %s" % ",".join(packages))
         print(traceback.format_exc())
 
-    # restore original settings of root logger
-    restore_root_logger(backup)
-
 
 def check_module(module_name, packages=None, pip_args=None):
     """