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I am unable to create multiple files with this code, what is wrong?

So I'm trying to write a program that takes names from a list and adds it to a letter. A text file is created for each name for the letter however the code seems to stop working at that point.
letter = []
names = []
file = open("Input/Letters/starting_letter.txt", "r")
letter = file.readlines()
file.close()
name1 = open("Input/Names/invited_names.txt", "r")
names = name1.readlines()
name1.close()
for name in names:
create_letter = open(f"{name}.txt", "w")
for line in letter:
line = line.replace("[name],", f"{name},")
create_letter.write(line)
create_letter.close()
I get the error message
Traceback (most recent call last):
File "C:\Users\Default User\PycharmProjects\Mail Merge Project Start\main.py", line 10, in <module>
create_letter = open(f"{name}.txt", "w")
OSError: [Errno 22] Invalid argument: 'Aang\n.txt'
Is there a problem with the way I am creating the files?

You can't have newlines in your file name. It is invalid in your OS/filesystem.
Remove them with:
open(f"{name.strip()}.txt", "w")
Or:
open(f"{name.replace('\n', '')}.txt", "w")

error Passing a String variable as filename to open a file

i have this problem: i'm tryna list all filenames from a directory and then print them with numbers on the left to let users select the file to use. Numbers are there because they match with the index of the position of filenames in the list. When i select a specific string filename in the list and pass it to
`f = open (filename, "r")
data = json.loads(f.read())`
i get:
Traceback (most recent call last):
File "test.py", line 170, in
data = json.loads(f.read())
AttributeError: 'str' object has no attribute 'loads'
full code:
jsons=glob.glob("*.json")
print(type(jsons))
print(type(jsons[0]))
n=0
if(jsons):
for json in jsons:
print(str(n) + ' - ' + json)
n=n+1
jsonselection=int(input('select your settings file: '))
filename=(" ".join(jsons[jsonselection].split()))
print()
print('your selection: ' + filename)
else:
sys.exit(colored('no json files available.','red'))
f = open (filename, "r")
data = json.loads(f.read())
actually if i pass to the method a random variable defined by me like name='file' it works.. i just can't understand why. Thanks in advance for the help

That would most likely be because of this line of code.
jsons=glob.glob("*.json")
and then you have
for json in jsons:

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)

Python inserting variable string as file name

I'm trying to create a file with a unique file name for every time my script runs. I am only intending to do this to every week or month. so I chose to use the date for the file name.
f = open('%s.csv', 'wb') %name
is where I'm getting this error.
Traceback (most recent call last):
File "C:\Users\User\workspace\new3\stjohnsinvoices\BabblevoiceInvoiceswpath.py", line 143, in <module>
f = open('%s.csv', 'ab') %name
TypeError: unsupported operand type(s) for %: 'file' and 'str'
it works if I use a static filename, is there an issue with the open function, that means you can't pass a string like this?
name is a string and has values such as :
31/1/2013BVI
Many thanks for any help.

You need to put % name straight after the string:
f = open('%s.csv' % name, 'wb')
The reason your code doesn't work is because you are trying to % a file, which isn't string formatting, and is also invalid.

you can do something like
filename = "%s.csv" % name
f = open(filename , 'wb')
or f = open('%s.csv' % name, 'wb')

Very similar to peixe.
You don't have to mention the number if the variables you add as parameters are in order of appearance
f = open('{}.csv'.format(name), 'wb')
Another option - the f-string formatting (ref):
f = open(f"{name}.csv", 'wb')

And with the new string formatting method...
f = open('{0}.csv'.format(name), 'wb')

Even better are f-strings in python 3!
f = open(f'{name}.csv', 'wb')

import hashlib
filename = file_for_download
with open(filename, "rb") as f:
bytes = f.read() # read entire file as bytes
msg_hash = hashlib.sha256(bytes).hexdigest();
print(f"MSG_HASH = {msg_hash}")

csv2json.py error

I am trying to run the script csv2json.py in the Command Prompt, but I get this error:
C:\Users\A\Documents\PROJECTS\Django\sw2>csv2json.py csvtest1.csv wkw1.Lawyer
Converting C:\Users\A\Documents\PROJECTS\Django\sw2csvtest1.csv from CSV to JSON as C:\Users\A\Documents\PROJECTS\Django\sw2csvtest1.csv.json
Traceback (most recent call last):
File "C:\Users\A\Documents\PROJECTS\Django\sw2\csv2json.py", line 37, in <module>
f = open(in_file, 'r' )
IOError: [Errno 2] No such file or directory: 'C:\\Users\\A\\Documents\\PROJECTS\\Django\\sw2csvtest1.csv'
Here are the relevant lines from the snippet:
31 in_file = dirname(__file__) + input_file_name
32 out_file = dirname(__file__) + input_file_name + ".json"
34 print "Converting %s from CSV to JSON as %s" % (in_file, out_file)
36 f = open(in_file, 'r' )
37 fo = open(out_file, 'w')
It seems that the directory name and file name are combined. How can I make this script run?
Thanks.
Edit:
Altering lines 31 and 32 as answered by Denis Otkidach worked fine. But I realized that the first column name needs to be pk and each row needs to start with an integer:
for row in reader:
if not header_row:
header_row = row
continue
pk = row[0]
model = model_name
fields = {}
for i in range(len(row)-1):
active_field = row[i+1]
So my csv row now looks like this (including the header row):
pk, firm_url, firm_name, first, last, school, year_graduated
1, http://www.graychase.com/aabbas, Gray & Chase, Amr A, Babas, The George Washington University Law School, 2005
Is this a requirement of the django fixture or json format? If so, I need to find a way to add the pk numbers to each row. Can I delete this pk column? Any suggestions?
Edit 2
I keep getting this ValidationError: "This value must be an integer". There is only one integer field and that's the pk. Is there a way to find out from the traceback what the line numbers refer to?
Problem installing fixture 'C:\Users\A\Documents\Projects\Django\sw2\wkw2\fixtures\csvtest1.csv.json': Traceback (most recent call last):
File "C:\Python26\Lib\site-packages\django\core\management\commands\loaddata.py", line 150, in handle
for obj in objects:
File "C:\Python26\lib\site-packages\django\core\serializers\json.py", line 41, in Deserializer
for obj in PythonDeserializer(simplejson.load(stream)):
File "C:\Python26\lib\site-packages\django\core\serializers\python.py", line 95, in Deserializer
data[field.attname] = field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
File "C:\Python26\lib\site-packages\django\db\models\fields\__init__.py", line 356, in to_python
_("This value must be an integer."))
ValidationError: This value must be an integer.

+ is used incorrectly here, the proper way to combine directory name and file name is using os.path.join(). But there is no need to combine directory where script is located with file name, since it's common to pass relative path to current working directory. So, change lines 31-32 to the following:
in_file = input_file_name
out_file = in_file + '.json'

from os import path
in_file = path.join(dirname(__file__), input_file_name )
out_file = path.join(dirname(__file__), input_file_name + ".json" )
[...]

You should be using os.path.join rather than just concatenating dirname() and filenames.
import os.path
in_file = os.path.join(dirname(__file__), input_file_name)
out_file = os.path.join(dirname(__file__), input_file_name + ".json")
will fix your problem, though depending on what exactly you're doing, there's probably a more elegant way to do it.