replace -1 with None for max_backoff_delay_seconds

pyworker/job.py

@@ -20,7 +20,7 @@ class Job(object, metaclass=Meta):
     def __init__(self, class_name, database, logger,
                  job_id, queue, run_at, attempts=0, max_attempts=1,
                  attributes=None, abstract=False, extra_fields=None,
-                 reporter=None, max_backoff_delay_seconds=-1):
+                 reporter=None, max_backoff_delay_seconds=None):
         super(Job, self).__init__()
         self.class_name = class_name
         self.database = database
@@ -146,7 +146,7 @@ def set_error_unlock(self, error):
             # set new exponential run_at
             setters.append('run_at = %s')
             delta = (self.attempts**4) + 5
-            if self.max_backoff_delay_seconds > 0 and delta > self.max_backoff_delay_seconds:
+            if self.max_backoff_delay_seconds and delta > self.max_backoff_delay_seconds:
                 delta = self.max_backoff_delay_seconds
             values.append(str(now + get_time_delta(seconds=delta)))