code: func (f *lightFetcher) isTrustedHash(hash common.Hash) bool {
  	if !f.pm.isULCEnabled() {
  		return true
  	}
  
  	var numAgreed int
  	for p, fp := range f.peers {
  		if !p.isTrusted {
  			continue
  		}
  		if _, ok := fp.nodeByHash[hash]; !ok {
  			continue
  		}
  
  		numAgreed++
  	}
  
  	return 100*numAgreed/len(f.pm.ulc.trustedKeys) >= f.pm.ulc.minTrustedFraction
  }
docs: // isTrustedHash checks if the block can be trusted by the minimum trusted fraction.