ContainsKeys determines if a set of label (keys) are present in a map of labels (keys and values).

IsEqualSubset compares the values of the given subset of keys between two maps and returns true if they are equal.

IsSubset compares two maps to determine if one of them is fully contained in the other.

Merge merges source into destination, overwriting existing values if necessary.

MergePreservingExistingKeys merges source into destination while skipping any keys that exist in the destination.