diff --git a/rq/cli/cli.py b/rq/cli/cli.py
index 95e8f3f..1486329 100755
--- a/rq/cli/cli.py
+++ b/rq/cli/cli.py
@@ -21,11 +21,11 @@ from rq.defaults import (DEFAULT_CONNECTION_CLASS, DEFAULT_JOB_CLASS,
                          DEFAULT_QUEUE_CLASS, DEFAULT_WORKER_CLASS,
                          DEFAULT_RESULT_TTL, DEFAULT_WORKER_TTL,
                          DEFAULT_JOB_MONITORING_INTERVAL,
-                         DEFAULT_LOGGING_FORMAT, DEFAULT_LOGGING_DATE_FORMAT)
+                         DEFAULT_LOGGING_FORMAT, DEFAULT_LOGGING_DATE_FORMAT,
+                         DEFAULT_SERIALIZER_CLASS)
 from rq.exceptions import InvalidJobOperationError
 from rq.registry import FailedJobRegistry, clean_registries
 from rq.utils import import_attribute
-from rq.serializers import DefaultSerializer
 from rq.suspension import (suspend as connection_suspend,
                            resume as connection_resume, is_suspended)
 from rq.worker_registration import clean_worker_registry
@@ -62,11 +62,11 @@ shared_options = [
                  default=DEFAULT_CONNECTION_CLASS,
                  help='Redis client class to use'),
     click.option('--path', '-P',
-                 default='.',
+                 default=['.'],
                  help='Specify the import path.',
                  multiple=True),
     click.option('--serializer', '-S',
-                 default=DefaultSerializer,
+                 default=DEFAULT_SERIALIZER_CLASS,
                  help='Path to serializer, defaults to rq.serializers.DefaultSerializer')
 ]
 
diff --git a/rq/defaults.py b/rq/defaults.py
index 701e356..227a1b6 100644
--- a/rq/defaults.py
+++ b/rq/defaults.py
@@ -1,6 +1,7 @@
 DEFAULT_JOB_CLASS = 'rq.job.Job'
 DEFAULT_QUEUE_CLASS = 'rq.Queue'
 DEFAULT_WORKER_CLASS = 'rq.Worker'
+DEFAULT_SERIALIZER_CLASS = 'rq.serializers.DefaultSerializer'
 DEFAULT_CONNECTION_CLASS = 'redis.Redis'
 DEFAULT_WORKER_TTL = 420
 DEFAULT_JOB_MONITORING_INTERVAL = 30
diff --git a/rq/utils.py b/rq/utils.py
index 284286b..6bbf7bf 100644
--- a/rq/utils.py
+++ b/rq/utils.py
@@ -137,11 +137,11 @@ def import_attribute(name):
             module_name = '.'.join(module_name_bits)
             module = importlib.import_module(module_name)
             break
-        except ModuleNotFoundError:
+        except ImportError:
             attribute_bits.insert(0, module_name_bits.pop())
 
     if module is None:
-        raise ValueError(f'Invalid attribute name: {name}')
+        raise ValueError('Invalid attribute name: %s' % name)
 
     attribute_name = '.'.join(attribute_bits)
     if hasattr(module, attribute_name):
@@ -153,7 +153,7 @@ def import_attribute(name):
     attribute_owner = getattr(module, attribute_owner_name)
 
     if not hasattr(attribute_owner, attribute_name):
-        raise ValueError(f'Invalid attribute name: {name}')
+        raise ValueError('Invalid attribute name: %s' % name)
 
     return getattr(attribute_owner, attribute_name)