human
I wrote the below code

    if (not _strptime):
        _strptime = datetime.datetime.strptime
    def import_date_time_lambda(value):
        if (not value):
            return None
        return _strptime(value, format)
    return import_date_time_lambda

What's a good function header?

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Here's a good function header?
assistant
#Here's a good function header.

def import_date_time(format, _strptime=None):