docs: def findall_operations(self, predicate: Callable[[ops.Operation], bool]
                             ) -> Iterable[Tuple[int, ops.Operation]]:
          """Find the locations of all operations that satisfy a given condition.
  
          This returns an iterator of (index, operation) tuples where each
          operation satisfies op_cond(operation) is truthy. The indices are
          in order of the moments and then order of the ops within that moment.
  
          Args:
              predicate: A method that takes an Operation and returns a Truthy
                  value indicating the operation meets the find condition.
  
          Returns:
              An iterator (index, operation)'s that satisfy the op_condition.
          """
          for index, moment in enumerate(self._moments):
              for op in moment.operations:
                  if predicate(op):
                      yield index, op