how to find the index number in python from a number in the array code example

Example 1: python find index of first matching element in a list

# Basic syntax:
list.index(element, start, end) 
# Where:
#	- Element is the item you're looking for in the list
# 	- Start is optional, and is the list index you want to start at
#	- End is option, and is the list index you want to stop searching at

# Note, Python is 0-indexed

# Example usage:
my_list = [1, 2, 3, 4, 5, 6, 7, 8, 42, 9, 10]
my_list.index(42)
--> 8

Example 2: position in array python

a_list = [1, 2, 3]

position_of_three = a_list.index(3)

print(position_of_three)