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Decrypt PDF with for loop

I am trying to run a for loop that scans lines of a txt and attempts to decrypt a PDF on every line. When it hits the right word, it should break and stop the loop. Here is my code. Please help.
import PyPDF2
dictionary = open('C:\\Users\\Admin\\Desktop\\Final Supporting Files\\dictionary.txt')
readDictionary = dictionary.readlines()
pdfReader = PyPDF2.PdfFileReader(
open('C:\\Users\\Admin\\Desktop\\Final Supporting Files\\encryptedhackme.pdf', 'rb'))
for line in readDictionary:
print(f'Do not stop the program, testing {line}')
if pdfReader.decrypt(line) == 1:
print(pdfReader.getPage(0))
break
elif pdfReader.decrypt(line.lower()) == 1:
print(pdfReader.getPage(0))
break
elif pdfReader.decrypt(line.title()) == 1:
print(pdfReader.getPage(0))
break
When I run this code, it is giving me an error that the line variable is an ordinal not in range. It returns an error message at the first line and I truly do not know why it is not working. I double checked and there doesn't seem to be any problem with the dictionary.txt file, it is many lines of words in plain text. Is there any insight as to why it isn't working?
Here is the error message
Traceback (most recent call last):
File "C:\Users\Admin\Desktop\Pycharm Projects\Final\PDF_Hacker.py", line 44, in <module>
main()
File "C:\Users\Admin\Desktop\Pycharm Projects\Final\PDF_Hacker.py", line 5, in main
hack()
File "C:\Users\Admin\Desktop\Pycharm Projects\Final\PDF_Hacker.py", line 31, in hack
if pdfReader.decrypt(key) == 1:
File "C:\Users\Admin\AppData\Local\Programs\Python\Python39\lib\site-packages\PyPDF2\pdf.py", line 1987, in decrypt
return self._decrypt(password)
File "C:\Users\Admin\AppData\Local\Programs\Python\Python39\lib\site-packages\PyPDF2\pdf.py", line 2017, in _decrypt
val = utils.RC4_encrypt(new_key, val)
File "C:\Users\Admin\AppData\Local\Programs\Python\Python39\lib\site-packages\PyPDF2\utils.py", line 181, in RC4_encrypt
retval += b_(chr(ord_(plaintext[x]) ^ t))
File "C:\Users\Admin\AppData\Local\Programs\Python\Python39\lib\site-packages\PyPDF2\utils.py", line 238, in b_
r = s.encode('latin-1')
UnicodeEncodeError: 'latin-1' codec can't encode character '\u014a' in position 0: ordinal not in range(256)

I'm using unpack in structure module in python and now getting errors

I'm now making a ransom-like program for my school project by using python module-struct, and there is struct.error: unpack requires a buffer of 8 bytes. I don't know why this is happening; because I was fixing codes in Github-it was not working in my computer-to understand how it works. And it does not work. At first, there was a problem in glob function and I fixed it, and I never touched this part.
I'm not used to using the struct module and didn't know how to use this function; so I tried to put only integer and remove 'infile.read(struct.calcsize('Q')) or insert '<' in front of Q in calcsize, or put only struct.calcsize('Q'). I also read docs and tried to understand how to use this and fix the problem but to my shame, I failed.
def decrypt_file(key, in_filename, out_filename = None, chnksize = 64*1024):
if not out_filename:
out_filename = os.path.splitext(in_filename)[0]
with open(in_filename, 'rb') as infile:
origsize = struct.unpack('<Q', infile.read(struct.calcsize('Q')))[0]
iv = infile.read(16)
decryptor = AES.new(key, AES.MODE_CBC, iv)
#chunksize = 16
with open(out_filename, 'wb') as outfile:
while True:
chunk = infile.read(chunksize)
if len(chunk) == 0:
break
outfile.write(decryptor.decrypt(chunk))
outfile.truncate(origsize)
It expected to decode the encoded file and firstly, it must calculate it's original size but it only spit out the error message-struct.error: unpack requires a buffer of 8 bytes.
It is the original error message:
C:\Users\Yeeun\Desktop\for Test\jmtree_44520.jpg .sasya
Decrypting> C:\Users\Yeeun\Desktop\for Test\jmtree_44520.jpg.sasya
Traceback (most recent call last):
File "C:\Users\Yeeun\Desktop\test\RansomTest.py", line 62, in <module>
decrypt_file(key, filename)
File "C:\Users\Yeeun\Desktop\test\RansomTest.py", line 32, in decrypt_file
origsize = struct.unpack('<Q', infile.read(struct.calcsize('Q')))[0]
struct.error: unpack requires a buffer of 8 bytes

reading last line of txt file in python and change it into variable to make calculation

td = 'date of transaction.txt'
tf = 'current balance.txt'
tr = 'transaction record.txt'
for line in open(tf):pass
for line2 in open(td):pass
for line3 in open(tr):pass
print line2,line,line3
"""
so call recall back last record
"""
rd=raw_input('\ndate of transaction: ')
print "Choose a type of transaction to proceed... \n\tA.Withdrawal \n\tB.Deposit \n\tC.Cancel & exit"
slc=raw_input('type of transaction: ')
i=1
while (i>0):
if slc=="A" or slc=="B" or slc=="C":
i=0
else:
i=i+1
slc=raw_input('invalid selection, please choose again...(A/B/C): ')
if slc=="A":
rr=input('\namount of transaction: ')
Line_len = 10 # or however long a line is, since in my example they all looked the same
SEEK_END = 2
file = open(tf, "r")
file.seek(-Line_len, SEEK_END)
a = int(str(file.read(Line_len)).split(" ")[0].strip())
rf=a-rr
f1=open(tf, 'a+')
f1.write('\n'+rf)
f1.close()
d1=open(td, 'a+')
d1.write('\n'+rd)
d1.close
r1=open(tr, 'a+')
r1.write('\n-'+rr)
r1.close
else:
print 'later'
above is my code, the function is to get data(last line) from txt file and read it, get new data and write it to the txt file again by creating new line.
my txt file(current balance.txt) should look like this:
2894.00
2694.00
but when i try to use the last line which is 2694.00 to do calculation(rf=a-rr), it failed returning this error:
Traceback (most recent call last):
File "C:\Python27\acc.py", line 27, in <module>
file.seek(-Line_len, SEEK_END)
IOError: [Errno 22] Invalid argument
else if i use this code:
for line in open(tf):
pass
a = line
rf=a-rr
it return this error:
Traceback (most recent call last):
File "C:\Python27\acc.py", line 27, in <module>
rf=a-rr
TypeError: unsupported operand type(s) for -: 'str' and 'int'
I seriously have no idea why...please help me...

To obtain last line of the file, you can simple do
with open('my_file.txt') as file:
last_line = file.readlines()[-1]
#last_line is a string value pointing to last line, to convert it into float, you can do
number = float(last_line.strip('\n').strip(' '))

The function input is giving you a string. Try doing:
rf=a-float(rr)

reading large JSON file in Python (raw_decode)

I am trying to read in large JSON file (data.json) in Python. Because the JSON file has multiple JSON objects, and multiple dictionaries will be created in Python(the number of dictionaries are unknown), I used decoder.raw_decode() and generator.
The following is the code:
import json
import pprint
import io
import pprint
def parse():
with open('data.json',encoding='utf-8') as jfile:
try:
while True:
decoder = json.JSONDecoder()
obj, idx = decoder.raw_decode(jfile)
yield obj
except ValueError as e:
print(e)
pass
else:
print("aha")
def main():
imputd=parse()
if imputd:
while True:
try:
print(str(next(imputd)).readlines())
except StopIteration as e:
print(e)
break
main()
I get the error:
Traceback (most recent call last):
File "H:\Document\Python\j10.py", line 57, in <module>
main()
File "H:\Document\Python\j10.py", line 36, in main
print(str(next(imputd)).readlines())
File "H:\Document\Python\j10.py", line 21, in parse
obj, idx = decoder.raw_decode(jfile)
File "C:\Python34\lib\json\decoder.py", line 360, in raw_decode
obj, end = self.scan_once(s, idx)
TypeError: first argument must be a string, not _io.TextIOWrapper
I edited code based on Martijn's answer:
import json
import io
file=open('data.json.txt')
def readin():
return file.read(2000)
def parse():
decoder = json.JSONDecoder()
buffer = ''
for chunk in iter(readin, ''):
buffer += chunk
while buffer:
try:
result, index = decoder.raw_decode(buffer)
yield result
buffer = buffer[index:]
except ValueError:
# Not enough data to decode, read more
break
def main():
imputd=parse()
if imputd:
while True:
try:
print(str(next(imputd)).readlines())
except StopIteration as e:
print(e)
break
main()
and I get an UnicodeError:
Traceback (most recent call last):
File "H:\Document\Python\j11.py", line 35, in <module>
main()
File "H:\Document\Python\j11.py", line 30, in main
print(str(next(imputd)).readlines())
File "H:\Document\Python\j11.py", line 14, in parse
for chunk in iter(readin, ''):
File "H:\Document\Python\j11.py", line 8, in readin
return file.read(2000)
File "C:\Python34\lib\encodings\cp1252.py", line 23, in decode
return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x9d in position 4217: character maps to <undefined>

You are passing in the file object, but decoder.raw_decode() only takes text data. You need to do the reading yourself:
obj, idx = decoder.raw_decode(jfile.read())
You are then yielding Python objects created from the JSON data, so your .readlines() call in your main() function loop will also fail.
You are not using raw_decode() correctly, however. You are yourself responsible for feeding it chunks of text, it'll not read that text from the file for you. If you wanted to handle the file in chunks, and there are no clear delimiters between the JSON entries, you'll be forced to read the file in blocks:
decoder = json.JSONDecoder()
buffer = ''
for chunk in iter(partial(jfile.read, buffersize), ''):
buffer += chunk
while buffer:
try:
result, index = decoder.raw_decode(buffer)
yield result
buffer = buffer[index:]
except ValueError:
# Not enough data to decode, read more
break
This will still yield completely decoded objects; if your file is one long JSON object (like one top-level list or dictionary) then this'll not yield the contents of that object one by one; it'll still read the whole object before yielding.

Replace given line in files in Python

I have several files, and I need to replace third line in them:
files = ['file1.txt', 'file2.txt']
new_3rd_line = 'new third line'
What is the best way to do this?
Files are big enough, several 100mb's files.

I used this solution: Search and replace a line in a file in Python
from tempfile import mkstemp
from shutil import move
from os import remove, close
def replace_3_line(file):
new_3rd_line = 'new_3_line\n'
#Create temp file
fh, abs_path = mkstemp()
new_file = open(abs_path,'w')
old_file = open(file)
counter = 0
for line in old_file:
counter = counter + 1
if counter == 3:
new_file.write(new_3rd_line)
else:
new_file.write(line)
#close temp file
new_file.close()
close(fh)
old_file.close()
#Remove original file
remove(file)
#Move new file
move(abs_path, file)
replace_3_line('tmp.ann')
But it does not work with files that contains non English charecters.
Traceback (most recent call last):
File "D:\xxx\replace.py", line 27, in <module>
replace_3_line('tmp.ann')
File "D:\xxx\replace.py", line 12, in replace_3_line
for line in old_file:
File "C:\Python31\lib\encodings\cp1251.py", line 23, in decode
return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x98 in position 32: character maps to <undefined>
That is bad. Where's python unicode? (file is utf8, python3).
File is:
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