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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 _clean_characters(x):
 """Clean problem characters in sample lane or descriptions. """

    if not isinstance(x, six.string_types):
        x = str(x)
    else:
        if not all(ord(char) < 128 for char in x):
            msg = "Found unicode character in input YAML (%s)" % (x)
            raise ValueError(repr(msg))
    for problem in [" ", ".", "/", "\\", "[", "]", "&", ";", "#", "+", ":", ")", "("]:
        x = x.replace(problem, "_")
    return x