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* Bugs
* [Issue 20] Automaton.Edge now returns an `AP` or `PL` class object for AP, PL, LTL.translate().
* [Issue 17] Unexpected AssertionError when calling `PL(st=..)` and `LTL(st=..)` is handled resolved.
* [Issue 16] Bug in the printing PL, LTL objects was resolved.
* Game module
* [Issue 6] Gridworld class accept ``p1_action`` and ``p2_action`` separately.
* [Issue 6] Gridworld class defined with basic 4, 5, 8, 9 connectivity.
* [Issue 23] Implement ``game.define(tsys, spec)`` function.
* [Issue 4] Defined ``Kripke`` class to support ``TSys`` class. No special properties or functions are
associated with ``Kripke`` are defined or implemented.
* [Issue 5] Updated ``TSys`` constructor signature to accept ``p1_action, p2_action`` instead of ``actions``.
``TSys.Vertex`` now requires ``name, turn`` parameters. ``turn = None`` represents a concurrent game.
``TSys.Edge`` is updated to represent both concurrent and turn-based edges.
* Solver module
* [Issue 24] ``ZielonkaSolver`` class defined and implemented. The solver computes winning regions only.
* Utilities
* [Issue 11] Added `has_vertex`, `has_edge`, `get_edges` functionality to `Graph` class.