sty: use deprecationwarning

Author: mgxd

nipype/interfaces/fsl/model.py

@@ -17,7 +17,6 @@
 import os
 from glob import glob
 from shutil import rmtree
-from warnings import warn
 
 import numpy as np
 from nibabel import load
@@ -1076,7 +1075,7 @@ class ContrastMgr(FSLCommand):
     corrections file is no longer generated by FILMGLS.
     """
     if Info.version() and LooseVersion(Info.version()) >= LooseVersion("5.0.7"):
-        warn("ContrastMgr is deprecated in FSL 5.0.7+", DeprecationWarning)
+        DeprecationWarning("ContrastMgr is deprecated in FSL 5.0.7+")
     _cmd = 'contrast_mgr'
     input_spec = ContrastMgrInputSpec
     output_spec = ContrastMgrOutputSpec