<s>[INST] Iterating over a string In C++, I could do:
for (int i = 0; i < str.length(); ++i)
    std::cout << str[i] << std::endl;

How do I iterate over a string in Python?
 [/INST] As Johannes pointed out, 
for c in "string":
    #do something with c

You can iterate pretty much anything in python using the for loop construct, 
for example, open("file.txt") returns a file object (and opens the file), iterating over it iterates over lines in that file
for line in open(filename):
    # do something with line

If that seems like magic, well it kinda is, but the idea behind it is really simple.  
There's a simple iterator protocol that can be applied to any kind of object to make the for loop work on it.
Simply implement an iterator that defines a next() method, and implement an __iter__ method on a class to make it iterable. (the __iter__ of course, should return an iterator object, that is, an object that defines next())
See official documentation
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