class_docstr: Abstract implementation of OAuth 1.0 and 1.0a.
  
  See `TwitterMixin` below for an example implementation.
  
  Class attributes:
  
  * ``_OAUTH_AUTHORIZE_URL``: The service's OAuth authorization url.
  * ``_OAUTH_ACCESS_TOKEN_URL``: The service's OAuth access token url.
  * ``_OAUTH_VERSION``: May be either "1.0" or "1.0a".
  * ``_OAUTH_NO_CALLBACKS``: Set this to True if the service requires
    advance registration of callbacks.
  
  Subclasses must also override the `_oauth_get_user_future` and
  `_oauth_consumer_token` methods.
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docstr: Returns the `.AsyncHTTPClient` instance to be used for auth requests.
  
  May be overridden by subclasses to use an HTTP client other than
  the default.
docstr_tok: ["Returns","the","`",".AsyncHTTPClient","`","instance","to","be","used","for","auth","requests",".","May","be","overridden","by","subclasses","to","use","an","HTTP","client","other","than","the","default","."]
code: def get_auth_http_client(self) -> httpclient.AsyncHTTPClient:
      """Returns the `.AsyncHTTPClient` instance to be used for auth requests.
  
      May be overridden by subclasses to use an HTTP client other than
      the default.
      """
      return httpclient.AsyncHTTPClient()
  
imports: import base64
  import binascii
  import hashlib
  import hmac
  import time
  import urllib.parse
  import uuid
  import warnings
  from tornado import httpclient
  from tornado import escape
  from tornado.httputil import url_concat
  from tornado.util import unicode_type
  from tornado.web import RequestHandler
  from typing import List, Any, Dict, cast, Iterable, Union, Optional
label_desc: Use image node_id 6 for calling the OAuthMixin obj's underlying member method code with example usage: obj.get_auth_http_client() and returns: httpclient