Apply suggestions from code review

Co-authored-by: Chris Markiewicz <effigies@gmail.com>

Author: JulianKlug

nibabel/imagestats.py

@@ -16,21 +16,23 @@
 def count_nonzero_voxels(img):
     """
     Count number of non-zero voxels
+
     Parameters
     ----------
     img : ``SpatialImage``
         All voxels of the mask should be of value 1, background should have value 0.
 
     Returns
     -------
-    non zero voxel volume: int
+    count : int
         Number of non-zero voxels
 
     """
     return np.count_nonzero(img.dataobj)
 
 def mask_volume(img):
     """ Compute volume of mask image.
+
     Equivalent to "fslstats /path/file.nii -V"
 
     Parameters
@@ -41,7 +43,7 @@ def mask_volume(img):
 
     Returns
     -------
-    mask_volume_mm3: float
+    volume : float
         Volume of mask expressed in mm3.
 
     Examples

nibabel/tests/test_imagestats.py

@@ -13,8 +13,6 @@
 from .. import imagestats
 from .. import Nifti1Image
 
-import pytest
-
 
 def test_mask_volume():
     # Test mask volume computation
@@ -28,4 +26,3 @@ def test_mask_volume():
 
     assert vol_mm3 == 1000.0
     assert vol_vox == 1000
-