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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _encode_datetime(obj):
 """Encode a msgpck'ed datetime."""


    if isinstance(obj, datetime.datetime):
        obj = {'__datetime__': True, 'as_str': obj.strftime("%Y%m%dT%H:%M:%S.%f").encode()}
    return obj