code: public static TypeSignature ofMap(Class<?> namedKeyType, Class<?> namedValueType) {
          return ofMap(ofNamed(namedKeyType, "namedKeyType"), ofNamed(namedValueType, "namedValueType"));
      }
docs: Creates a new type signature for the map with the specified named key and value types.
  This method is a shortcut of:
  <pre>{@code
  ofMap(ofNamed(namedKeyType), ofNamed(namedValueType));
  }</pre>