Why I cannot use transforms.ifft2?

I have the following imports

import h5py
import numpy as np
import matplotlib.pyplot as plt
import torch
from fastmri.data import transforms

After some lines of code I have the following two line:

slice_kspace2=transforms.to_tensor(slice_kspace)
slice_image=transforms.ifft2(slice_kspace2)

The first line works fine so transforms.to_tensor is fine but not the second line I get the following error.

File "testForF.py", line 32, in <module>
    slice_image=transforms.ifft2(slice_kspace2)
AttributeError: module 'fastmri.data.transforms' has no attribute 'ifft2'

Any help please. Where can I find the "transforms" which has ifft2, that all the people are using while working on fastMRI data?

from Why I cannot use transforms.ifft2?