code: def truthy(self):
          ''' Recognize a Boolean-like string value as a Boolean.
              Note: the rules are a bit different than string "truthiness."
  
              '0'             --> False
              '1'             --> True
              ('no', 'false') --> False  # case-insensitive
              ('yes', 'true') --> True   # case-insensitive
          '''
          lower = self.lower()
          if lower.isdigit():
              return bool(int(lower))
          elif lower in ('yes', 'true'):
              return True
          elif lower in ('no', 'false'):
              return False
          elif self == '':
              return False
          else:
              return Nonf truthy(self):
          ''' Recognize a Boolean-like string value as a Boolean.
              Note: the rules are a bit different than string "truthiness."
  
              '0'             --> False
              '1'             --> True
              ('no', 'false') --> False  # case-insensitive
              ('yes', 'true') --> True   # case-insensitive
          '''
          lower = self.lower()
          if lower.isdigit():
              return bool(int(lower))
          elif lower in ('yes', 'true'):
              return True
          elif lower in ('no', 'false'):
              return False
          elif self == '':
              return False
          else:
              return None
docs: Recognize a Boolean-like string value as a Boolean.
              Note: the rules are a bit different than string "truthiness."
  
              '0'             --> False
              '1'             --> True
              ('no', 'false') --> False  # case-insensitive
              ('yes', 'true') --> True   # case-insensitive