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* Use of builtin now works with Python 2 & 3.
* Started using namedtuple in some places (like net traversal) for clarity.
* Corrected pin-to-pin connections so if a net is created, it goes into the same Circuit the pins are members of.
* Part templates can now contain a reference to a Circuit object that will be applied when the template is instantiated.
* When pins are connected to nets, or nets to nets, the resulting set of connected nets are all given the same name.
* Buses are not added to a Circuit object if they are already members of it. This fix caused the next problem.
* Buses weren't getting added to the Circuit object because they already contained a reference to the Circuit. Fixed by clearing ref before adding to Circuit.
* Created mini_reset() method to clear circuitry without clearing library cache so the libraries don't have to be loaded again (slow).
* search() utility now prints the names of libraries as they are searched so user sees progress.
* Fixed exceptions if part definition contained non-unicode stuff.
* Hide exceptions that occur when using the show() utility.
* More tests added for NC nets and hand-crafted parts.
* default_circuit and the NC net for the active circuit are now made accessible in all modules using __builtin__.
* Corrected error messages that referenced wrong/non-existing variable.
* Inserted NO_LIB for the library if it doesn't exist when generating KiCad netlists or XML.
* Attributes can now be passed when creating a Circuit object.
* Pins are now associated with part when added to the part.
* Minimum and maximum pins for a part are now computed as needed.
* Each Circuit object now has its own NC net.
* Added tests for bus movement and copying.
* Implemented bus movement between Circuit objects.
* Additional test cases were created.
* Nets and Parts can now be removed from Circuits.
* The circuit that pins and nets are in is now checked before connections are made so cross-circuit connections are not created.
* Default members were added to Pin and Part objects so they would always exist and not cause errors when missing.
* Implemented moving Parts and Nets from one circuit to another (almost).
* Nets with no attached pins are now added to a circuit.
* Re-wrote some tests to account for the presence of no-pin nets in a circuit.
* A class method was missing its 'self' argument.
* Fixed subcircuit decorator so it won't cause an error if the function it decorates doesn't have a 'circuit' keyword argument.
* Split the unit tests across multiple files. Added setup/teardown code.
* Added capability to create multiple, independent Circuit objects to which Parts and Nets can be assigned. The default circuit is still the target if not Circuit is explicitly referenced.
* Added IOError to exception list for opening a SKiDL part library.