How to tell when a method is called for first time of many

Question

I would like to be able to tell when a method has been called for the first time. I primarily need this for when I am printing out to a delimited file, and if it is the first iteration, I would like to print a header before the actual information. This is what I normally do:

def writeFile(number, count):
    if count == 1:
        print('number')
        print(str(count))
    else:
        print(str(count))


count = 1
for i in range(10):
    writeFile(i, count)
    count += 1

This provides the following output:

number
1
2
3
4
5
6
7
8
9
10

Though this achieves the goal I am after, I am curious as to if there is a better/more efficient way of doing this. Is there some way to detect if a method has been called for the first time without having to pass an additional argument to it?

Thank you,

Answer 1

There are multiple ways to do this. Here are three.

First:

firstRun=True
def writeFile(number):
    global firstRun
    if firstRun:
        print('number')
        firstRun=False
    print(str(number))

for i in range(10):
    writeFile(i)

Second:

def writeFile(number):
    print(str(number))

for i in range(10):
    if not i:
        print('number')
    writeFile(i)

Third:

for i in range(10):
    print(('' if i else 'number\n')+str(i))

I'm assuming this is just a test problem meant to indicate cases where function calls initialize or reset data. I prefer ones that hide the information from the calling function (such as 1). I am new to Python, so I may be using bad practices.