I am new to Python and please excuse if my question sounds dumb. I have a function which reads a text file and records the first line and passes the same to another function. But I am not able to figure out a way to store the value to a global variable which can be reused again. 

Sample of text file. Holds only one line:
1234567 

Script to read file:

```
def main():
    input = file(infile, 'r')
    lines = input.readlines()
    input.close()
    i = 0
    for line in lines:
        i += 1
        id = int(line)
        WorkOnIDThread(id)
main()

```

So basically I want help with storing the id as a global variable which I could reuse through out the script. 

Any help on this would be really helpful.