substring

This seems like it should be pretty trivial, but I am new at Python and want to do it the most Pythonic way.
I want to find the index corresponding to the n’th occurrence of a substring within a string.
There’s got to be something equivalent to what I WANT to do which is
mystring.find(“substring”, 2nd)
How can you achieve this in Python?
….

How can I get a string after a specific substring?
For example, I want to get the string after “world” in
my_string=”hello python world, I’m a beginner”

…which in this case is: “, I’m a beginner”)
….

This question already has answers here:

Does Python have a string ‘contains’ substring method?

(10 answers)

Closed 8 years ago.

I have two strings and I would like to check whether the first is a substring of the other. Does….

This question already has answers here:

How to extract the substring between two markers?

(21 answers)

Closed 4 years ago.

How do I find a string between two substrings (‘123STRINGabc’ -> ‘STRING’)?
My current method is like….

Let’s say I have a string ‘gfgfdAAA1234ZZZuijjk’ and I want to extract just the ‘1234’ part.
I only know what will be the few characters directly before AAA, and after ZZZ the part I am interested in 1234.
With sed it is possible to do something like this with a string:
echo “$STRING” | sed -e “s|.*AAA\(.*\)ZZZ.*|\1|”

And this will give me 1234 a….

I want to get a new string from the third character to the end of the string, e.g. myString[2:end]. If omitting the second part means ’till the end’, and if you omit the first part, does it start from the start?
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