code: def can_map_ipa_string(self, ipa_string):
          
          canonical = [(c.canonical_representation, ) for c in ipa_string]
          split = split_using_dictionary(canonical, self, self.max_key_length, single_char_parsing=False)
          for sub in split:
              if not sub in self.ipa_canonical_representation_to_mapped_str:
                  return False
          return True
docs: Return ``True`` if the mapper can map all the IPA characters
          in the given IPA string.
  
          :param IPAString ipa_string: the IPAString to be parsed
          :rtype: bool