externalState: It may be an external state or data, that is, data obtained from an external source, such as data obtained from an API, is stored in this variable.
unavailableCapabilities: May refer to unavailable functions or capabilities, possibly a list of functions or capabilities that are not available in a program or system.
instance: It may be used to store the instance number or identifier of the object, which is used to distinguish and manage multiple object instances of the same or different types.
internalState: May be internal state or data, i.e. stored or computed state inside the program. This variable may contain temporary data when the program is running, such as calculation intermediate results, status identifiers, etc.