chore: Remove six library and __future__ imports (#646)

Closes: SDK-1876

Author: lukaszsocha2

boxsdk/__init__.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals, absolute_import
-
 from .auth import JWTAuth, OAuth2
 from .client import *  # pylint:disable=wildcard-import,redefined-builtin
 from .exception import *  # pylint:disable=wildcard-import

boxsdk/auth/__init__.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals
-
 from .cooperatively_managed_oauth2 import CooperativelyManagedOAuth2
 from .developer_token_auth import DeveloperTokenAuth
 try:

boxsdk/auth/cooperatively_managed_oauth2.py

@@ -1,6 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals
 from .oauth2 import OAuth2
 
 

boxsdk/auth/developer_token_auth.py

@@ -1,9 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals, absolute_import
-
-from six.moves import input  # pylint:disable=redefined-builtin
-
 from .oauth2 import OAuth2
 
 

boxsdk/auth/jwt_auth.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import absolute_import, unicode_literals
-
 from datetime import datetime, timedelta
 import json
 import random
@@ -12,13 +10,11 @@
 from cryptography.hazmat.primitives import serialization
 from cryptography.hazmat.primitives.asymmetric.rsa import RSAPrivateKey
 import jwt
-from six import binary_type, string_types, raise_from, text_type
 
 from ..config import API
 from ..exception import BoxOAuthException
 from .oauth2 import OAuth2
 from ..object.user import User
-from ..util.compat import NoneType
 
 
 class JWTAuth(OAuth2):
@@ -254,7 +250,7 @@ def _auth_with_jwt(self, sub, sub_type):
                 if attempt_number >= API.MAX_RETRY_ATTEMPTS:
                     raise ex
 
-                if (code == 429 or code >= 500):
+                if code == 429 or code >= 500:
                     jwt_time = None
                 elif box_datetime is not None and self._was_exp_claim_rejected_due_to_clock_skew(network_response):
                     jwt_time = box_datetime
@@ -365,8 +361,8 @@ def _normalize_user_id(cls, user):
             return None
         if isinstance(user, User):
             return user.object_id
-        if isinstance(user, string_types):
-            return text_type(user)
+        if isinstance(user, str):
+            return str(user)
         raise TypeError("Got unsupported type {0!r} for user.".format(user.__class__.__name__))
 
     def authenticate_instance(self, enterprise=None):
@@ -423,15 +419,15 @@ def _normalize_rsa_private_key(cls, file_sys_path, data, passphrase=None):
                 data = key_file.read()
         if hasattr(data, 'read') and callable(data.read):
             data = data.read()
-        if isinstance(data, text_type):
+        if isinstance(data, str):
             try:
                 data = data.encode('ascii')
-            except UnicodeError:
-                raise_from(
-                    TypeError("rsa_private_key_data must contain binary data (bytes/str), not a text/unicode string"),
-                    None,
-                )
-        if isinstance(data, binary_type):
+            except UnicodeError as unicode_error:
+                raise TypeError(
+                    "rsa_private_key_data must contain binary data (bytes/str), not a text/unicode string"
+                ) from unicode_error
+
+        if isinstance(data, bytes):
             passphrase = cls._normalize_rsa_private_key_passphrase(passphrase)
             return serialization.load_pem_private_key(
                 data,
@@ -450,15 +446,15 @@ def _normalize_rsa_private_key(cls, file_sys_path, data, passphrase=None):
 
     @staticmethod
     def _normalize_rsa_private_key_passphrase(passphrase):
-        if isinstance(passphrase, text_type):
+        if isinstance(passphrase, str):
             try:
                 return passphrase.encode('ascii')
-            except UnicodeError:
-                raise_from(
-                    TypeError("rsa_private_key_passphrase must contain binary data (bytes/str), not a text/unicode string"),
-                    None,
-                )
-        if not isinstance(passphrase, (binary_type, NoneType)):
+            except UnicodeError as unicode_error:
+                raise TypeError(
+                    "rsa_private_key_passphrase must contain binary data (bytes/str), not a text/unicode string"
+                ) from unicode_error
+
+        if not isinstance(passphrase, (bytes, type(None))):
             raise TypeError(
                 "rsa_private_key_passphrase must contain binary data (bytes/str), got {0!r}"
                 .format(passphrase.__class__.__name__)

boxsdk/auth/oauth2.py

@@ -1,18 +1,11 @@
 # coding: utf-8
 
-from __future__ import unicode_literals
-
 from contextlib import contextmanager
 from logging import getLogger
 import random
 import string  # pylint:disable=deprecated-module
-import sys
 from threading import Lock
-
-# pylint:disable=import-error,no-name-in-module
-from six.moves.urllib.parse import urlencode, urlunsplit
-# pylint:enable=import-error,no-name-in-module
-import six
+from urllib.parse import urlunsplit, urlencode
 
 from ..config import API
 from ..exception import BoxOAuthException, BoxAPIException
@@ -489,19 +482,19 @@ def closing(self, **close_kwargs):
         # pylint:disable=broad-except
         try:
             yield self
-        except Exception:
-            exc_infos.append(sys.exc_info())
-        except BaseException:
-            exc_infos.append(sys.exc_info())
+        except Exception as exception:
+            exc_infos.append(exception)
+        except BaseException as base_exception:
+            exc_infos.append(base_exception)
             close_kwargs['revoke'] = False
 
         try:
             self.close(**close_kwargs)
-        except Exception:
-            exc_infos.append(sys.exc_info())
+        except Exception as exception:
+            exc_infos.append(exception)
 
         if exc_infos:
-            six.reraise(*exc_infos[0])
+            raise exc_infos[0]
 
     def _check_closed(self):
         if self.closed:

boxsdk/auth/redis_managed_jwt_auth.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals, absolute_import
-
 from .jwt_auth import JWTAuth
 from .redis_managed_oauth2 import RedisManagedOAuth2Mixin
 

boxsdk/auth/redis_managed_oauth2.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals
-
 from uuid import uuid4
 
 from redis import StrictRedis

boxsdk/auth/remote_managed_oauth2.py

@@ -1,6 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals
 from .oauth2 import OAuth2
 
 

boxsdk/client/__init__.py

@@ -1,7 +1,5 @@
 # coding: utf-8
 
-from __future__ import unicode_literals, absolute_import
-
 from .client import Client
 from .developer_token_client import DeveloperTokenClient
 from .development_client import DevelopmentClient