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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 print_declarations( decls, detailed=True, recursive=True, writer=lambda x: sys.stdout.write(x + os.linesep), verbose=True):
 """ print declarations tree rooted at each of the included nodes. :param decls: either a single :class:declaration_t object or list of :class:declaration_t objects """

    prn = decl_printer_t(0, detailed, recursive, writer, verbose=verbose)
    if not isinstance(decls, list):
        decls = [decls]
    for d in decls:
        prn.level = 0
        prn.instance = d
        algorithm.apply_visitor(prn, d)