code: func (b *Bucket) openBucket(value []byte) *Bucket {
  	var child = newBucket(b.tx)
  
  	// If unaligned load/stores are broken on this arch and value is
  	// unaligned simply clone to an aligned byte array.
  	unaligned := brokenUnaligned && uintptr(unsafe.Pointer(&value[0]))&3 != 0
  
  	if unaligned {
  		value = cloneBytes(value)
  	}
  
  	// If this is a writable transaction then we need to copy the bucket entry.
  	// Read-only transactions can point directly at the mmap entry.
  	if b.tx.writable && !unaligned {
  		child.bucket = &bucket{}
  		*child.bucket = *(*bucket)(unsafe.Pointer(&value[0]))
  	} else {
  		child.bucket = (*bucket)(unsafe.Pointer(&value[0]))
  	}
  
  	// Save a reference to the inline page if the bucket is inline.
  	if child.root == 0 {
  		child.page = (*page)(unsafe.Pointer(&value[bucketHeaderSize]))
  	}
  
  	return &child
  }
docs: // Helper method that re-interprets a sub-bucket value
  // from a parent into a Bucket