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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 fold_string(input_string, max_width):
 """ Fold a string within a maximum width. Parameters: input_string: The string of data to go into the cell max_width: Maximum width of cell. Data is folded into multiple lines to fit into this width. Return: String representing the folded string """

    new_string = input_string
    if isinstance(input_string, six.string_types):
        if max_width < len(input_string):
            # use textwrap to fold the string
            new_string = textwrap.fill(input_string, max_width)

    return new_string