fix can't raise invalid expire time when set px param is 0

1 files changed, 1 insertions, 1 deletions

diff --git a/redis/client.py b/redis/client.py
index 30a56a2..14d424d 100755
--- a/redis/client.py
+++ b/redis/client.py
@@ -1155,7 +1155,7 @@ class StrictRedis(object):
             if isinstance(ex, datetime.timedelta):
                 ex = ex.seconds + ex.days * 24 * 3600
             pieces.append(ex)
-        if px:
+        if px is not None:
             pieces.append('PX')
             if isinstance(px, datetime.timedelta):
                 ms = int(px.microseconds / 1000)