Why is binary file bigger?

Question

I created a compressor for my online course project using huffman algorithm. Problem is that the output file in binary (10101010011..) is bigger than the original files.

Teachers on the course don't know the answer.

I use this, where ciph_text is a string of 0s and 1s.

with open(full_name,'w') as temp:
    temp.write(ciph_text)

Any idea?
I can post more code if requested.

Answer 1

int(x, 2) is your friend:

>>> a="00001010000101000001111000101000"
>>> for b in range(0, len(a), 8):
...   print a[b:b+8], int(a[b:b+8], 2)
... 
00001010 10
00010100 20
00011110 30
00101000 40