I can't use DurationField

[Body Abdo]

 
I get error :
ValueError: Enter a valid duration.

When i'm importing excel file - i'm using postgresql
my models.py

An Series class - for describe series in the system
"""
id = models.CharField(max_length=20)
program = models.CharField(max_length=100)
tape = models.CharField(max_length=100)
duration = models.DurationField()