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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 stylize(txt, bold=False, underline=False):
 """ Changes style of the text. """


    setting = ''
    setting += _SET_BOLD if bold is True else ''
    setting += _SET_UNDERLINE if underline is True else ''
    return setting + str(txt) + _STYLE_RESET