> For the complete documentation index, see [llms.txt](https://george-jen.gitbook.io/data-science-and-apache-spark/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://george-jen.gitbook.io/data-science-and-apache-spark/functions-and-methods.md).

# Functions and methods

### Functions and methods

Python functions or methods return or do not have to return values

```
def fib(n): # write Fibonacci series up to n
    a, b = 0, 1
    while a<n:
        print(a, end=' ')
        a,b = b,a+b
    print("")

fib(10)

#0 1 1 2 3 5 8 
```