Use simple string concatenation not triple quotes

nbconvert/exporters/pdf.py

@@ -94,9 +94,9 @@ def run_command(self, command_list, filename, count, log_function):
         cmd = which(command_list[0])
         if cmd is None:
             link = "https://nbconvert.readthedocs.io/en/latest/install.html#installing-tex"
-            raise OSError("""{formatter} not found on PATH, if you have not installed
-                             {formatter} you may need to do so. Find further instructions
-                             at {link}.""".format(formatter=command_list[0], link=link))
+            raise OSError("{formatter} not found on PATH, if you have not installed "
+                          "{formatter} you may need to do so. Find further instructions "
+                          "at {link}.".format(formatter=command_list[0], link=link))
 
         times = 'time' if count == 1 else 'times'
         self.log.info("Running %s %i %s: %s", command_list[0], count, times, command)