How to index a string in Python 3 ?

String index( ) Method

 The index() method determines if the string str occurs in string or in a substring of string,if the starting index beg and ending index end are given. This method is same as find(),but raises an exception if sub is not found.

Syntax

str.index(str, beg=0 end=len(string))

Parameters

· str - This specifies the string to be searched.

· beg - This is the starting index, by default its 0.

· end - This is the ending index, by default its equal to the length of the string.

Return Value

Index if found otherwise raises an exception if str is not found.

Example

#!/usr/bin/python3 str1 = "this is string example....wow!!!" str2 = "exam"; print (str1.index(str2)) print (str1.index(str2, 10)) print (str1.index(str2, 40))

Result

15 15 Traceback (most recent call last):     File "test.py", line 7, in       print (str1.index(str2, 40)) ValueError: substring not found shell returned 1

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