def nii_ones_like(in_file, value, dtype, newpath=None):
    """Create a NIfTI file filled with ``value``, matching properties of ``in_file``"""
    import os
    import numpy as np
    import nibabel as nb

    nii = nb.load(in_file)
    data = np.ones(nii.shape, dtype=float) * value

    out_file = os.path.join(newpath or os.getcwd(), "filled.nii.gz")
    nii = nb.Nifti1Image(data, nii.affine, nii.header)
    nii.set_data_dtype(dtype)
    nii.to_filename(out_file)

    return out_file
Create a NIfTI file filled with ``value``, matching properties of ``in_file``