Add copyright and license to pip's files

Copyright notice is based on original pip copyright:
	Copyright @ 2008-2021 The pip developers (see AUTHORS.txt file). All
	rights reserved.
The year was removed being unnecessary and AUTHORS file name was
adjusted.

Signed-off-by: Alexander Mazuruk <a.mazuruk@samsung.com>

Author: aalexanderr

src/fetchcode/vcs/pip/__init__.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 from fetchcode.vcs.pip._internal.utils import _log
 
 _log.init_logging()

src/fetchcode/vcs/pip/_internal/exceptions.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 """Exceptions used throughout package"""
 
 from itertools import groupby

src/fetchcode/vcs/pip/_internal/utils/_log.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 """Customize logging
 
 Defines custom logger class for the `logger.verbose(...)` method.

src/fetchcode/vcs/pip/_internal/utils/compat.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 """Stuff that differs in different Python versions and platform
 distributions."""
 

src/fetchcode/vcs/pip/_internal/utils/logging.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 import contextlib
 import errno
 import logging

src/fetchcode/vcs/pip/_internal/utils/misc.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 # The following comment should be removed at some point in the future.
 # mypy: strict-optional=False
 

src/fetchcode/vcs/pip/_internal/utils/subprocess.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 import logging
 import os
 import shlex

src/fetchcode/vcs/pip/_internal/utils/temp_dir.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 import errno
 import itertools
 import logging

src/fetchcode/vcs/pip/_internal/utils/urls.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 import os
 import string
 import urllib.parse

tests/conftest.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: MIT
+# Copyright @ The pip developers (see pip-AUTHORS.txt). All rights reserved
+
 import os
 import shutil
 import sys