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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 bytes(num, check_result=False):
 """ Returns num bytes of cryptographically strong pseudo-random bytes. If checkc_result is True, raises error if PRNG is not seeded enough """


    if num <= 0:
        raise ValueError("'num' should be > 0")
    buf = create_string_buffer(num)
    result = libcrypto.RAND_bytes(buf, num)
    if check_result and result == 0:
        raise RandError("Random Number Generator not seeded sufficiently")
    return buf.raw[:num]