Problem description - https://drive.google.com/file/d/1TCiPO44wODkrh1i6WrFmbS4M1OeFIzbc/view

traceback_log_parsing.py

# Enter your code here. Read input from STDIN. Print output to STDOUT

BACKTRACE_START_STR = 'Traceback '
BACKTRACE_END_STR = 'raise '
BACKTRACE_SEPARATOR = '-' * 50

def search_and_print_backtrace(logs):
    line = 0
    is_backtrace = False
    is_first_backtrace = True
    while line < len(logs):
        if BACKTRACE_START_STR in logs[line]:
            is_backtrace = True
            log_columns = logs[line].count(']')
            if not is_first_backtrace:
                print BACKTRACE_SEPARATOR
            is_first_backtrace = False
            
        if is_backtrace:
            # Remove starting space and print only last column
            print ']'.join(logs[line].split(']')[log_columns:])[1:]
            
        if BACKTRACE_END_STR in logs[line]:
            print ']'.join(logs[line +  1].split(']')[log_columns:])[1:]
            is_backtrace = False
            line += 1
        line += 1
        
def main():
    raw_logs = []
    while True:
        try:
            raw_logs.append(raw_input())
        except:
            break
    search_and_print_backtrace(raw_logs)
    

if __name__ == '__main__':
    main()