Given a string and a search term, find the index of the first occurrence of the search term in the string.
String: hello world
Search term: wor
The index of the first occurrence of the search term 'wor' in the string 'hello world' is 6.
Complete the following task based on the instruction and optional input provided.### Instruction:
Given a string and a search term, find the index of the first occurrence of the search term in the string.

### Input:
String: hello world
Search term: wor

### Output:
The index of the first occurrence of the search term 'wor' in the string 'hello world' is 6.