Short way to serialize datetime with marshmallow

If it does not work, use the keyword format

started_at = fields.DateTime(format='%Y-%m-%dT%H:%M:%S+03:00')

I would rather use datetimeformat, see: https://marshmallow.readthedocs.io/en/3.0/api_reference.html

Example:

class MyVisitSchema(Schema):
    cafe = fields.Nested(CafeSchema)
    started_at = fields.DateTime()
    ended_at = fields.DateTime()

    class Meta:
        additional = ('duration',)
        ordered = True
        # dateformat = '%Y-%m-%dT%H:%M:%S%z'
        dateformat = '%Y-%m-%dT%H:%M:%S+03:00'

And I prefer to:

class BaseSchema(Schema):
    class Meta:
        dateformat = '%Y-%m-%dT%H:%M:%S+03:00'


class MyVisitSchema(BaseSchema):
    cafe = fields.Nested(CafeSchema)
    started_at = fields.DateTime()
    ended_at = fields.DateTime()

    class Meta(BaseSchema.Meta):
        additional = ('duration',)
        ordered = True

Found some info in official documentaries. So, my issue can be solved using

started_at = fields.DateTime('%Y-%m-%dT%H:%M:%S+03:00')

hardcode a bit, but looks better than using additional function with fields.Method()