[Tutor] string to binary and back... Python 3

[Jordan]

OK so I have been trying for a couple days now and I am throwing in the
towel, Python 3 wins this one.
I want to convert a string to binary and back again like in this
question: Stack Overflow: Convert Binary to ASCII and vice versa
(Python)
<http://stackoverflow.com/questions/7396849/convert-binary-to-ascii-and-vice-versa-python>
But in Python 3 I consistently get  some sort of error relating to the
fact that nothing but bytes and bytearrays support the buffer interface
or I get an overflow error because something is too large to be
converted to bytes.
Please help me and then explian what I am not getting that is new in
Python 3. I would like to point out I realize that binary, hex, and
encodings are all a very complex subject and so I do not expect to
master it but I do hope that I can gain a deeper insight. Thank you all.

test_script.py:
import binascii

test_int = 109

test_int = int(str(test_int) + '45670')
data = 'Testing XOR Again!'

while sys.getsizeof(data) > test_int.bit_length():

test_int = int(str(test_int) + str(int.from_bytes(os.urandom(1), 'big')))

print('Bit Length: ' + str(test_int.bit_length()))

key = test_int # Yes I know this is an unnecessary step...

data = bin(int(binascii.hexlify(bytes(data, 'UTF-8')), 16))

print(data)

data = int(data, 2)

print(data)

data = binascii.unhexlify('%x' % data)


wolfrage at lm12-laptop02 ~/Projects $ python3 test_script.py
Bit Length: 134
0b10101000110010101110011011101000110100101101110011001110010000001011000010011110101001000100000010000010110011101100001011010010110111000100001
7351954002991226380810260999848996570230305
Traceback (most recent call last):
File "test_script.py", line 24, in <module>
data = binascii.unhexlify('%x' % data)
TypeError: 'str' does not support the buffer interface



test_script2.py:
import binascii
test_int = 109
test_int = int(str(test_int) + '45670')
data = 'Testing XOR Again!'
while sys.getsizeof(data) > test_int.bit_length():
test_int = int(str(test_int) + str(int.from_bytes(os.urandom(1), 'big')))
print('Bit Length: ' + str(test_int.bit_length()))
key = test_int # Yes I know this is an unnecessary step...
data = bin(int(binascii.hexlify(bytes(data, 'UTF-8')), 16))
print(data)
data = int(data, 2)
print(data)
data = binascii.unhexlify(bytes(data, 'utf8'))



wolfrage at lm12-laptop02 ~/Projects $ python3 test_script2.py
Bit Length: 140
0b10101000110010101110011011101000110100101101110011001110010000001011000010011110101001000100000010000010110011101100001011010010110111000100001
7351954002991226380810260999848996570230305
Traceback (most recent call last):
File "test_script.py", line 24, in <module>
data = binascii.unhexlify(bytes(data, 'utf8'))
OverflowError: cannot fit 'int' into an index-sized integer