Python · Interactive Mode & First Steps

Assigning to a dictionary key that doesn't exist yet — what happens? ``` >>> d = {"key1": "value1"} >>> d["key3"] = "value3" ```

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More in Interactive Mode & First Steps

What does this scientific-notation literal evaluate to, and what type is it? ``` >>> 12.345e3 ```

You type a literal at the >>> prompt and want to know its data type without guessing. What do you do?

At the >>> prompt you type a bare expression and press Enter. What does the interactive interpreter do with the result?

The REPL auto-echoes a string differently from how print shows it. What does each line below produce? ``` >>> "Hello World" >>> print("Hello World") ```

In the interactive mode, what does the underscore _ refer to, and where does this NOT work?

An assignment like x = 5 is a statement, not an expression. What does the REPL print right after you enter it?

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