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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 right(ctx, text, num_chars):
 """ Returns the last characters in a text string """

    num_chars = conversions.to_integer(num_chars, ctx)
    if num_chars < 0:
        raise ValueError("Number of chars can't be negative")
    elif num_chars == 0:
        return ''
    else:
        return conversions.to_string(text, ctx)[-num_chars:]