PEP8 and header warning (doc)

Author: kastman

doc/source/dicom/dicom_niftiheader.rst

@@ -52,6 +52,11 @@ Creating a PMOD-compatible header is just as easy::
     >> nim.header.extensions.append(dcmext)
     >> nib.save(nim,'pet_withdcm.nii')
 
+Be careful! Many imaging tools don't maintain information in the extended
+header, so it's possible [likely] that this information may be lost during
+routine use. You'll have to keep track, and re-write the information if
+required.
+
 .. _`NIfTI Extensions Standard`: http://nifti.nimh.nih.gov/nifti-1/documentation/nifti1fields/nifti1fields_pages/extension.html
 
 .. include:: links_names.txt

nibabel/nifti1.py

@@ -412,25 +412,25 @@ def _guess_implicit_VR(self):
         valid VRs"""
         potential_vr = self._raw_content[4:6].decode()
         if potential_vr in dicom_converters.keys():
-            implicit_VR=False
+            implicit_VR = False
         else:
-            implicit_VR=True
+            implicit_VR = True
         return implicit_VR
 
     def _guess_little_endian(self):
         return True
 
-    def _unmangle(self,value):
-        bio=BytesIO(value)
-        ds=read_dataset(bio,self._is_implicit_VR,self._is_little_endian)
+    def _unmangle(self, value):
+        bio = BytesIO(value)
+        ds = read_dataset(bio, self._is_implicit_VR, self._is_little_endian)
         return ds
 
     def _mangle(self, dataset):
-        bio=BytesIO()
-        dio=DicomFileLike(bio)
+        bio = BytesIO()
+        dio = DicomFileLike(bio)
         dio.is_implicit_VR = self._is_implicit_VR
         dio.is_little_endian = self._is_little_endian
-        ds_len=write_dataset(dio,dataset)
+        ds_len = write_dataset(dio, dataset)
         dio.seek(0)
         return dio.read(ds_len)