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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 banner():
 """ Display a product banner :return: a delightful Mesosphere logo rendered in unicode :rtype: str """


    banner_dict = {
        'a0': click.style(chr(9601), fg='magenta'),
        'a1': click.style(chr(9601), fg='magenta', bold=True),
        'b0': click.style(chr(9616), fg='magenta'),
        'c0': click.style(chr(9626), fg='magenta'),
        'c1': click.style(chr(9626), fg='magenta', bold=True),
        'd0': click.style(chr(9622), fg='magenta'),
        'd1': click.style(chr(9622), fg='magenta', bold=True),
        'e0': click.style(chr(9623), fg='magenta'),
        'e1': click.style(chr(9623), fg='magenta', bold=True),
        'f0': click.style(chr(9630), fg='magenta'),
        'f1': click.style(chr(9630), fg='magenta', bold=True),
        'g1': click.style(chr(9612), fg='magenta', bold=True),
        'h0': click.style(chr(9624), fg='magenta'),
        'h1': click.style(chr(9624), fg='magenta', bold=True),
        'i0': click.style(chr(9629), fg='magenta'),
        'i1': click.style(chr(9629), fg='magenta', bold=True),
        'j0': click.style(fchr('>>'), fg='magenta'),
        'k0': click.style(chr(9473), fg='magenta'),
        'l0': click.style('_', fg='magenta'),
        'l1': click.style('_', fg='magenta', bold=True),
        'v0': click.style('mesosphere', fg='magenta'),
        'x1': click.style('shakedown', fg='magenta', bold=True),
        'y0': click.style('v' + shakedown.VERSION, fg='magenta'),
        'z0': chr(32)
    }

    banner_map = [
        " %(z0)s%(z0)s%(l0)s%(l0)s%(l1)s%(l0)s%(l1)s%(l1)s%(l1)s%(l1)s%(l1)s%(l1)s%(l1)s%(l1)s",
        " %(z0)s%(b0)s%(z0)s%(c0)s%(z0)s%(d0)s%(z0)s%(z0)s%(z0)s%(z0)s%(e1)s%(z0)s%(f1)s%(z0)s%(g1)s",
        " %(z0)s%(b0)s%(z0)s%(z0)s%(c0)s%(z0)s%(h0)s%(e0)s%(d1)s%(i1)s%(z0)s%(f1)s%(z0)s%(z0)s%(g1)s%(z0)s%(j0)s%(v0)s %(x1)s %(y0)s",
        " %(z0)s%(b0)s%(z0)s%(z0)s%(f0)s%(c0)s%(i0)s%(z0)s%(z0)s%(h1)s%(f1)s%(c1)s%(z0)s%(z0)s%(g1)s%(z0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(k0)s%(z0)s%(k0)s%(k0)s%(z0)s%(z0)s%(k0)s",
        " %(z0)s%(i0)s%(f0)s%(h0)s%(z0)s%(z0)s%(c0)s%(z0)s%(z0)s%(f0)s%(z0)s%(z0)s%(i1)s%(c1)s%(h1)s",
        " %(z0)s%(z0)s%(z0)s%(z0)s%(z0)s%(z0)s%(z0)s%(c0)s%(f0)s",
    ]

    if 'TERM' in os.environ and os.environ['TERM'] in ('velocity', 'xterm', 'xterm-256color', 'xterm-color'):
        return echo("\n".join(banner_map) % banner_dict)
    else:
        return echo(fchr('>>') + 'mesosphere shakedown v' + shakedown.VERSION, b=True)