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Python 3.0 Strings in Action

Let’s step through a few examples that demonstrate how the 3.0 string types are used. One note up front: the code in this section was run with and applies to 3.0 only. Still, basic string operations are generally portable across Python versions. Simple ASCII strings represented with the str type work the same in 2.6 and 3.0 (and exactly as we saw in Chapter 7 of this book). Moreover, although there is no bytes type in Python 2.6 (it has just the general str), it can usually run code that thinks there is—in 2.6, the call bytes(X) is present as a synonym for str(X), and the new literal form b'...' is taken to be the same as the normal string literal '...'. You may still run into version skew in some isolated cases, though; the 2.6 bytes call, for instance, does not allow the second argument (encoding name) required by 3.0’s bytes.