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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 _to_s(val, sep=", "):
 """Convert any to string. :param val: An object :param sep: separator between values '1, 2, 3' 'aaa' """

    if anyconfig.utils.is_iterable(val):
        return sep.join(str(x) for x in val)

    return str(val)