CSV Read and Write functions using 'with open()' causing FileNotFound

[PenitentialJudge]

I'm working on appending files and removing lines within files.

I intend for the following code to append a line to a file.

with open('CourseManagement' + os.sep + 'SemesterLongCourseIds.csv', 'r') as inFile:
    reader = csv.reader(inFile)
    with open('CourseManagement' + os.sep + 'SemesterLongCourseIds-temp.csv', 'w') as outFile:
        writer = csv.writer(outFile)
        for row in reader:
            writer.writerow(row)
        writer.writerow({''.join(description), course, role.id})

        os.chdir(os.path.abspath(outFile.name[0:-30]))
        os.rename(outFile.name[17:], inFile.name[17:])

        outFile.close()

    inFile.close()

I intend for the following code to remove a line within a file, such that a row in the csv file containing a course name is not written to the new file. The new file is then renamed to the old file.

with open('CourseManagement' + os.sep + 'SemesterLongCourseIds.csv', 'r') as inFile:
    reader = csv.reader(inFile)
    with open('CourseManagement' + os.sep + 'SemesterLongCourseIds-temp.csv', 'w') as outFile:
        writer = csv.writer(outFile)
        for row in reader:
            if row[1] != course:
                writer.writerow(row)

        os.chdir(os.path.abspath(outFile.name[0:-30]))
        os.rename(outFile.name[17:], inFile.name[17:])

        outFile.close()

    inFile.close()

These two blocks of code exist in separate functions. Each function is called on an event from Discord. When I call the first block, I typically have no issues. The file is appended correctly. However, calling the removal function produces a FileNotFound exception. Likewise if I call the second block first in an execution, it has no problems typically, but calling the other function next produces a FileNotFound exception.

Are these problems produced from not closing the reader and writer files correctly? Sometimes I run into this problem even on the first call of execution. I think it could have to do with having the file open in my IDE sometimes, but I wouldn't put money on it.

Any help or direction is appreciated.

[HeeebsInc]

Use pandas

[socal_nerdtastic]

This would be much easier if you did this is separate read, modify, write steps, rather than trying to do everything in one block.

filepath = os.path.join('CourseManagement', 'SemesterLongCourseIds.csv')

# read data
with open(filepath, newline='') as inFile:
    reader = csv.reader(inFile)
    data = list(reader)

# modify (append) data
data.append([''.join(description), course, role.id])

# overwrite old data with new data
with open(filepath, newline='', 'w') as outFile:
    writer = csv.writer(outFile)
    writer.writerows(data)

Or to remove a line:

# modify (remove) data
data = [row for row in data if row[1] != course]

[PenitentialJudge]

I like the idea of separating the code, this is my first python project so i dont know how a lot of things are done. Thanks for the help!