How to use the rsa._compat.byte function in rsa

"""

    warnings.warn("The 'rsa.bigfile.encrypt_bigfile' function was deprecated in Python-RSA version "
                  "3.4 due to security issues in the VARBLOCK format. See "
                  "https://stuvel.eu/python-rsa-doc/usage.html#working-with-big-files "
                  "for more information.",
                  DeprecationWarning, stacklevel=2)

    if not isinstance(pub_key, key.PublicKey):
        raise TypeError('Public key required, but got %r' % pub_key)

    key_bytes = common.bit_size(pub_key.n) // 8
    blocksize = key_bytes - 11  # keep space for PKCS#1 padding

    # Write the version number to the VARBLOCK file
    outfile.write(byte(varblock.VARBLOCK_VERSION))

    # Encrypt and write each block
    for block in varblock.yield_fixedblocks(infile, blocksize):
        crypto = pkcs1.encrypt(block, pub_key)

        varblock.write_varint(outfile, len(crypto))
        outfile.write(crypto)

def test_struct_error_when_out_of_bounds(self):
        self.assertRaises(struct.error, byte, 256)
        self.assertRaises(struct.error, byte, -1)

def int2bytes(number):
    """Converts a number to a string of bytes
    """

    if not (type(number) is types.LongType or type(number) is types.IntType):
        raise TypeError("You must pass a long or an int")

    string = ""

    while number > 0:
        string = "%s%s" % (byte(number & 0xFF), string)
        number /= 256
    
    return string

raise TypeError("You must pass a long or an int")

    if 0 <= number <= 9:            #00-09 translates to '0' - '9'
        return byte(number + 48)

    if 10 <= number <= 35:
        return byte(number + 55)     #10-35 translates to 'A' - 'Z'

    if 36 <= number <= 61:
        return byte(number + 61)     #36-61 translates to 'a' - 'z'

    if number == 62:                # 62   translates to '-' (minus)
        return byte(45)

    if number == 63:                # 63   translates to '_' (underscore)
        return byte(95)

    raise ValueError('Invalid Base64 value: %i' % number)

"""

    if not (type(number) is types.LongType or type(number) is types.IntType):
        raise TypeError("You must pass a long or an int")

    if 0 <= number <= 9:            #00-09 translates to '0' - '9'
        return byte(number + 48)

    if 10 <= number <= 35:
        return byte(number + 55)     #10-35 translates to 'A' - 'Z'

    if 36 <= number <= 61:
        return byte(number + 61)     #36-61 translates to 'a' - 'z'

    if number == 62:                # 62   translates to '-' (minus)
        return byte(45)

    if number == 63:                # 63   translates to '_' (underscore)
        return byte(95)

    raise ValueError('Invalid Base64 value: %i' % number)

# there is a big difference between 'write the value 0' (this case) and
    # 'there is nothing left to write' (the false-case of the while loop)

    if value == 0:
        outfile.write(ZERO_BYTE)
        return 1

    written_bytes = 0
    while value > 0:
        to_write = value & 0x7f
        value = value >> 7

        if value > 0:
            to_write |= 0x80

        outfile.write(byte(to_write))
        written_bytes += 1

    return written_bytes

if number == 0:
        needed_bytes = 1
        raw_bytes = [ZERO_BYTE]
    else:
        needed_bytes = common.byte_size(number)
        raw_bytes = []

    # You cannot compare None > 0 in Python 3x. It will fail with a TypeError.
    if block_size and block_size > 0:
        if needed_bytes > block_size:
            raise OverflowError('Needed %i bytes for number, but block size '
                                'is %i' % (needed_bytes, block_size))

    # Convert the number to bytes.
    while number > 0:
        raw_bytes.insert(0, byte(number & 0xFF))
        number >>= 8

    # Pad with zeroes to fill the block
    if block_size and block_size > 0:
        padding = (block_size - needed_bytes) * ZERO_BYTE
    else:
        padding = EMPTY_BYTE

    return padding + EMPTY_BYTE.join(raw_bytes)

"""Reads 'nbits' random bits.

    If nbits isn't a whole number of bytes, an extra byte will be appended with
    only the lower bits set.
    """

    nbytes, rbits = divmod(nbits, 8)

    # Get the random bytes
    randomdata = os.urandom(nbytes)

    # Add the remaining random bits
    if rbits > 0:
        randomvalue = ord(os.urandom(1))
        randomvalue >>= (8 - rbits)
        randomdata = byte(randomvalue) + randomdata

    return randomdata