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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 rpad(s, N, char='\0'):
 """pads a string to the right with null-bytes or any other given character. ..note:: This is used by the :py:func:`xor` function. :param s: the string :param N: an integer of how much padding should be done :returns: the original bytes """

    assert isinstance(char, bytes) and len(char) == 1, 'char should be a string with length 1'
    return s.ljust(N, char)