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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 ts_to_str(jwt_dict):
 """Convert timestamps in JWT to human readable dates. Args: jwt_dict: dict JWT with some keys containing timestamps. Returns: dict: Copy of input dict where timestamps have been replaced with human readable dates. """

    d = ts_to_dt(jwt_dict)
    for k, v in list(d.items()):
        if isinstance(v, datetime.datetime):
            d[k] = v.isoformat().replace('T', ' ')
    return d