old_contents: from validator.BaseValidator import BaseValidator
  from validate_email import validate_email
  class EmailValidator(BaseValidator):
  
      message = "Value is not correct email address"
  
      def validate(self, value):
  
          #possible null values
          if value is None:
              return True
  
          value = super(EmailValidator, self).validate(value)
          if type(value) is str or type(value) is str:
              return  validate_email(value)
  
          return False
  
      def __init__(self, params):
          super(EmailValidator, self).__init__(params)
  
  
new_contents: from validator.BaseValidator import BaseValidator
  from validate_email import validate_email
  class EmailValidator(BaseValidator):
  
      message = "Value is not correct email address"
  
      def validate(self, value):
  
          #possible null values
          if value is None:
              return True
  
          value = super(EmailValidator, self).validate(value)
          if type(value) is str:
              return  validate_email(value)
  
          return False
  
      def __init__(self, params):
          super(EmailValidator, self).__init__(params)
  
  
subject: Update EmailValidator.py