code: def contains_ignoring_case(self, *items):
          
          if len(items) == 0:
              raise ValueError('one or more args must be given')
          if isinstance(self.val, str_types):
              if len(items) == 1:
                  if not isinstance(items[0], str_types):
                      raise TypeError('given arg must be a string')
                  if items[0].lower() not in self.val.lower():
                      self._err('Expected <%s> to case-insensitive contain item <%s>, but did not.' % (self.val, items[0]))
              else:
                  missing = []
                  for i in items:
                      if not isinstance(i, str_types):
                          raise TypeError('given args must all be strings')
                      if i.lower() not in self.val.lower():
                          missing.append(i)
                  if missing:
                      self._err('Expected <%s> to case-insensitive contain items %s, but did not contain %s.' % (self.val, self._fmt_items(items), self._fmt_items(missing)))
          elif isinstance(self.val, Iterable):
              missing = []
              for i in items:
                  if not isinstance(i, str_types):
                      raise TypeError('given args must all be strings')
                  found = False
                  for v in self.val:
                      if not isinstance(v, str_types):
                          raise TypeError('val items must all be strings')
                      if i.lower() == v.lower():
                          found = True
                          break
                  if not found:
                      missing.append(i)
              if missing:
                  self._err('Expected <%s> to case-insensitive contain items %s, but did not contain %s.' % (self.val, self._fmt_items(items), self._fmt_items(missing)))
          else:
              raise TypeError('val is not a string or iterable')
          return self
docs: Asserts that val is string and contains the given item or items.