code: def leaves_are_consistent(self):
          
          self.log(u"Checking if leaves are consistent")
          leaves = self.leaves()
          if len(leaves) < 1:
              self.log(u"Empty leaves => return True")
              return True
          min_time = min([l.interval.begin for l in leaves])
          self.log([u"  Min time: %.3f", min_time])
          max_time = max([l.interval.end for l in leaves])
          self.log([u"  Max time: %.3f", max_time])
          self.log(u"  Creating SyncMapFragmentList...")
          smf = SyncMapFragmentList(
              begin=min_time,
              end=max_time,
              rconf=self.rconf,
              logger=self.logger
          )
          self.log(u"  Creating SyncMapFragmentList... done")
          self.log(u"  Sorting SyncMapFragmentList...")
          result = True
          not_head_tail = [l for l in leaves if not l.is_head_or_tail]
          for l in not_head_tail:
              smf.add(l, sort=False)
          try:
              smf.sort()
              self.log(u"  Sorting completed => return True")
          except ValueError:
              self.log(u"  Exception while sorting => return False")
              result = False
          self.log(u"  Sorting SyncMapFragmentList... done")
          return result
docs: Return ``True`` if the sync map fragments
          which are the leaves of the sync map tree
          (except for HEAD and TAIL leaves)
          are all consistent, that is,
          their intervals do not overlap in forbidden ways.
  
          :rtype: bool
  
          .. versionadded:: 1.7.0