New api for mixing

[harley]

@rickwierenga

or even worse, non-matching parameters.

Completely agree! I have been thinking about this since posting this issue: Mismatched mixing parameters for aspirate + dispense

@rickwierenga

with the new api it’s clear which belong together (although in your specific case repetitions and mix_speed are the same between mix volumes)

Also agree. I see this being similar to how we use the Coordinate object for offset parameter, where users may stash a couple Mix variables to be called in aspirate/dispense:

fast_mix = Mix(volume=100, repetitions=10, flow_rate=500)
slow_mix = Mix(volume=100, repetitions=3, flow_rate=50)

await lh.dispense(... mix=[fast_mix]*6+[slow_mix]*2)