Fix import in the test due to move + use str() since now tostring is gone

Author: yarikoptic

heudiconv/heuristics/convertall_custom.py

@@ -18,7 +18,7 @@ def custom_seqinfo(series_files, wrapper, **kw):  # noqa: U100
     from nibabel.nicom.dicomwrappers import WrapperError
 
     try:
-        affine = wrapper.affine.tostring()
+        affine = str(wrapper.affine)
     except WrapperError:
         lgr.exception("Errored out while obtaining/converting affine")  # noqa: F405
         affine = None

heudiconv/tests/test_dicoms.py

@@ -102,7 +102,7 @@ def test_group_dicoms_into_seqinfos() -> None:
 def test_custom_seqinfo() -> None:
     """Tests for custom seqinfo extraction"""
 
-    from heudiconv.heuristics.convertall import custom_seqinfo
+    from heudiconv.heuristics.convertall_custom import custom_seqinfo
 
     dcmfiles = glob(op.join(TESTS_DATA_PATH, "phantom.dcm"))