Sample axes code from Reproduce in Python produces axes that are uneven and don't match the API

[anth-volk]

We generate 401 axes in the API, corresponding with $500 increments from $0 to $200,000. However, the Reproduce in Python page defaults to 200 increments, creating increments of $1,000.03 from $0 to $200k, which is a bit strange and doesn't accord with our use of axes in the API. Seems more logical to change the count to 401.