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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 _build_option_description(k):
 """ Builds a formatted description of a registered option and prints it """


    o = _get_registered_option(k)
    d = _get_deprecated_option(k)

    s = '{k} '.format(k=k)

    if o.doc:
        s += '\n'.join(o.doc.strip().split('\n'))
    else:
        s += 'No description available.'

    if o:
        s += ('\n    [default: {default}] [currently: {current}]'
              .format(default=o.defval, current=_get_option(k, True)))

    if d:
        s += '\n    (Deprecated'
        s += (', use `{rkey}` instead.'
              .format(rkey=d.rkey if d.rkey else ''))
        s += ')'

    return s