manipulate JSON-like data with NumPy-like idioms

 Awkward Array is a library for nested, variable-sized data, including
 arbitrary-length lists, records, mixed types, and missing data, using
 NumPy-like idioms.
 .
 Arrays are dynamically typed, but operations on them are compiled and fast.
 Their behavior coincides with NumPy when array dimensions are regular and
 generalizes when they're not.