As reported by @halldalton on gitter.im, aggregate works as expected, however aggregateByKey fails.

@rahulyesantharao detected the cause, which is using get_lambda_source which has been deprecated in favor of a combined function to extract both functions defined via def and lambda expressions.

Example code which results in buggy behavior:

tups.aggregateByKey(
    lambda a, b: a + b,
    lambda a, x: a + x["volume"],
    0.0,
    ["id"]
)