code: def check_case_sensitivity (self):
          
          if os.name != 'nt':
              return
          path = self.get_os_filename()
          realpath = get_nt_filename(path)
          if path != realpath:
              self.add_warning(_("The URL path %(path)r is not the same as the "
                              "system path %(realpath)r. You should always use "
                              "the system path in URLs.") % \
                              {"path": path, "realpath": realpath},
                                 tag=WARN_FILE_SYSTEM_PATH)
docs: Check if url and windows path name match cases
          else there might be problems when copying such
          files on web servers that are case sensitive.