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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 _create_readme(fmt, reffmt):
    '''
    Creates the readme file for the bundle

    Returns a str representing the readme file
    '''

    now = datetime.datetime.utcnow()
    timestamp = now.strftime('%Y-%m-%d %H:%M:%S UTC')

    # yapf: disable
    outstr = _readme_str.format(timestamp=timestamp,
                                bsever=api.version(),
                                fmt=fmt, reffmt=reffmt)
    # yapf: enable

    return outstr