new_contents: class XMLError(SyntaxError):
      """Incorrect XML was sent to API"""
  
  
  class PhoneError(ValueError):
      """Incorrect phone of recipient"""
  
  
  class StartTimeError(ValueError):
      """Incorrect start time for sending messages"""
  
  
  class EndTimeError(ValueError):
      """Incorrect end time of campaign"""
  
  
  class StartTimeError(ValueError):
      """Incorrect start time of campaign"""
  
  
  class LifetimeError(ValueError):
      """Incorrect lifetime of campaign"""
  
  
  class SpeedError(ValueError):
      """Incorrect speed for sending messages"""
  
  
  class AlphanameError(NameError):
      """The name is forbidden for use, or there's an error in it"""
  
  
  class TextError(ValueError):
      """Incorrect text of message"""
  
  
  class InsufficientFundsError(Exception):
      """Insufficient funds. Unable to send messages"""
  
subject: Create custom error classes