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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 guess_chimera_path(search_all=False):
 """ Try to guess Chimera installation path. Parameters search_all : bool, optional, default=False If no CHIMERADIR env var is set, collect all posible locations of Chimera installations. Returns ------- paths: list of str Alphabetically sorted list of possible Chimera locations """

    paths = _search_chimera(CHIMERA_BINARY, CHIMERA_LOCATIONS, CHIMERA_PREFIX,
                            search_all=search_all)
    if not paths and search_all:  # try headless?
        headless = '{0[0]}{1}{0[1]}'.format(os.path.split(CHIMERA_BINARY), '-headless')
        paths = _search_chimera(headless, CHIMERA_LOCATIONS, CHIMERA_PREFIX,
                                search_all=search_all)
    if not paths:
        sys.exit("Could not find UCSF Chimera.\n{}".format(_INSTRUCTIONS))
    return paths