The isDirtycommand is used to check if a plug is dirty. The return value is 0 if it is not and 1 if it is. If more than one plug is specified then the result is the logical orof all objects (ie. returns 1 if *any* of the plugs are dirty).
Check the connection of the plug (default). Flag can have multiple arguments, passed either as a tuple or a list.
Check the datablock entry for the plug.
Derived from mel command maya.cmds.isDirty