<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def load_neurite_features(filepath):
    '''Unpack relevant data into megadict'''
    stuff = defaultdict(lambda: defaultdict(list))
    nrns = nm.load_neurons(filepath)
    # unpack data into arrays
    for nrn in nrns:
        for t in NEURITES_:
            for feat in FEATURES:
                stuff[feat][str(t).split('.')[1]].extend(
                    nm.get(feat, nrn, neurite_type=t)
                )
    return stuff