class_docstr: Holds an array of fits and allows access to their attributes and
  methods
class_docstr_tok: ["Holds","an","array","of","fits","and","allows","access","to","their","attributes","and","methods"]
code: def __getitem__(self, index):
      item = self.fit_array[index]
      if isinstance(item, np.ndarray):
          return MultiVoxelFit(self.model, item, self.mask[index])
      else:
          return item
  
file_path: dipy/dipy/reconst/multi_voxel.py
imports: import numpy
  from numpy.lib.stride_tricks import as_strided
  from tqdm import tqdm
  from dipy.core.ndindex import ndindex
  from dipy.reconst.quick_squash import quick_squash
  from dipy.reconst.base import ReconstFit
label_desc: Use image node_id 4 for calling the MultiVoxelFit obj's underlying member method code with example usage: obj.__getitem__(index) and returns: MultiVoxelFit, item