old_contents: import os
  
  from twilio.exceptions import TwilioException
  
  
  def get_cert_file():
      """ Get the cert file location or bail """
      # XXX - this currently fails test coverage because we don't actually go
      # over the network anywhere. Might be good to have a test that stands up a
      # local server and authenticates against it.
      try:
          # Apparently __file__ is not available in all places so wrapping this
          # in a try/catch
          current_path = os.path.realpath(__file__)
          ca_cert_path = os.path.join(current_path, '..', '..', 'conf', 'cacert.pem')
          return os.path.abspath(ca_cert_path)
      except Exception:
          # None means use the default system file
          return None
  
  
  class HttpClient(object):
      def request(self,
                  method,
                  url,
                  params=None,
                  data=None,
                  headers=None,
                  auth=None,
                  timeout=None,
                  allow_redirects=False):
          raise TwilioException('HttpClient is an abstract class')
  
new_contents: import os
  
  from twilio.exceptions import TwilioException
  
  
  def get_cert_file():
      """ Get the cert file location or bail """
      # XXX - this currently fails test coverage because we don't actually go
      # over the network anywhere. Might be good to have a test that stands up a
      # local server and authenticates against it.
      try:
          # Apparently __file__ is not available in all places so wrapping this
          # in a try/catch
          current_path = os.path.realpath(__file__)
          ca_cert_path = os.path.join(current_path, '..', '..', 'conf', 'cacert.pem')
          return os.path.abspath(ca_cert_path)
      except Exception:
          # None means use the default system file
          return None
  
  
  class HttpClient(object):
      """
      An abstract class representing an HTTP client.
      """
      def request(self, method, url, params=None, data=None, headers=None, auth=None,
                  timeout=None, allow_redirects=False):
          """
          Make an HTTP request.
          """
          raise TwilioException('HttpClient is an abstract class')
  
subject: Document `http/__init__.py`