- c_tag_start = ls.find('<coordinates>')
- c_start = c_tag_start + len('<coordinates>')
- c_end = ls.find('</coordinates>')
+ c_tag_start = ls.find(Coordinates.OPEN_TAG)
+ c_start = c_tag_start + len(Coordinates.OPEN_TAG)
+ c_end = ls.find(Coordinates.CLOSE_TAG)