Substring Between

[oldoc63]

We need a function that is able to extract a portion of a string between two characters. The function will take three parameters where the first parameter is the string we are going to extract the substring from, the second input is the starting character of our substring and the third character is the ending character of our substring. Here are the steps we can use:

1. Define the function to accept three parameters, one string and two characters
2. find the starting index of our substring using the second input parameter
3. find the ending index of our substring using the third input parameter
4. If neither of the indices are -1, return the portion of the first input parameter string between the starting and ending indices (not including the starting and ending index)
5. If either of the indices are -1, that means the start or end of the substring didn't exist in our string. Return the original string in this case.
6. https://www.w3schools.com/python/ref_string_find.asp

[oldoc63]

We use the find function to get the starting and ending indices of our substring using our starting and ending characters. After getting those, we check to make sure neither of them are -1. In order to extract the portion of the string within those indices, we use slicing. We provide the starting index plus one in order to not include the starting character. We do not need to provide the end index plus one, since the value on the right of the colon is excluded. This causes our slicing looks like: word[start_ind+1:end_ind]