- a `Path` is a better description for an instance of the model
- the `Location`s en route are renamed into `.waypoints`
- generic `assoc` is renamed into `path` in the test suite
- as of September 2021, PyCharm is used to write some of the code
- PyCharm's built-in code styler, linter, and type checker issued
some warnings that are resolved in this commit
+ spelling mistakes
+ all instance attributes must be specified explicitly
in a class's __init__() method
=> use `functools.cached_property` for caching
+ make `tuple`s explicit with `(...)`
+ one test failed randomly although everything is ok
=> adjust the fixture's return value (stub for Google Directions API)
+ reformulate SQL so that PyCharm can understand the symbols
- `DistanceMatrix.from_addresses()` takes a variable number of
`Address` objects and creates distance matrix entries for them
- as a base measure, the air distance between two `Address`
objects is calculated
- in addition, an integration with the Google Maps Directions API is
implemented that provides a more realistic measure of the distance
and duration a rider on a bicycle would need to travel between two
`Address` objects
- add a `Location.lat_lng` convenience property that provides the
`.latitude` and `.longitude` of an `Address` as a 2-`tuple`
- the class stores the data of a distance matrix between all addresses
+ air distances
+ bicycle distances
- in addition, the "path" returned by the Google Directions API are
also stored as a JSON serialized sequence of latitude-longitude pairs
- we assume a symmetric graph
