Sincerely, I had the same problem trying to parse the date and time using RequestParser, and unfortunately the docs are not very useful for this scenario, so after looking and testing the RequestParser and Argument code, I think I found the problem :
type=datetime add_argument, datetime arg, : datetime(arg), , , : 2016-07-12T23:13:3, an integer is required.
%Y-%m-%dT%H:%M:%S datetime, - type=datetime.strptime , , , , :
parser.add_argument('date', type=lambda x: datetime.strptime(x,'%Y-%m-%dT%H:%M:%S'))
, , . partial functool lambda, .
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