<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _is_inside(self, span1, span2, covered_spans):
 """Returns True if both `span1` and `span2` fall within `covered_spans`. :param span1: start and end indices of a span :type span1: 2-`tuple` of `int` :param span2: start and end indices of a span :type span2: 2-`tuple` of `int` :param covered_spans: lists of start and end indices for parts of the texts already covered by a sequence :type covered_spans: `list` of two `list`s of 2-`tuple` of `int` :rtype: `bool` """

        if self._is_span_inside(span1, covered_spans[0]) and \
           self._is_span_inside(span2, covered_spans[1]):
            return True
        return False