code: def check_authorization(self):
  		
  		try:
  			store = self.__config.get('basic_auth')
  			if store is None:
  				return True
  			auth_info = self.headers.get('Authorization')
  			if not auth_info:
  				return False
  			auth_info = auth_info.split()
  			if len(auth_info) != 2 or auth_info[0] != 'Basic':
  				return False
  			auth_info = base64.b64decode(auth_info[1]).decode(sys.getdefaultencoding())
  			username = auth_info.split(':')[0]
  			password = ':'.join(auth_info.split(':')[1:])
  			password_bytes = password.encode(sys.getdefaultencoding())
  			if hasattr(self, 'custom_authentication'):
  				if self.custom_authentication(username, password):
  					self.basic_auth_user = username
  					return True
  				return False
  			if not username in store:
  				self.server.logger.warning('received invalid username: ' + username)
  				return False
  			password_data = store[username]
  
  			if password_data['type'] == 'plain':
  				if password == password_data['value']:
  					self.basic_auth_user = username
  					return True
  			elif hashlib.new(password_data['type'], password_bytes).digest() == password_data['value']:
  				self.basic_auth_user = username
  				return True
  			self.server.logger.warning('received invalid password from user: ' + username)
  		except Exception:
  			pass
  		return False
docs: Check for the presence of a basic auth Authorization header and
  		if the credentials contained within in are valid.
  
  		:return: Whether or not the credentials are valid.
  		:rtype: bool