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So p=mv normally but why does ∆p = 2mv when a molecule or something hits a wall and comes back? v is velocity and when using velocity direction matter 阅读全文
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A typical event-driven program is not doing anything most of the time, and its functionality is only triggered by external signals, such as user input 阅读全文
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with statement Here is the syntax of the with statement: with expression as var: statements The expression should be a context manager object, or it s 阅读全文
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Figure 20.4: Built-in exceptions The class BaseException is the base class of all the built-in exception classes. From BaseException, four classes nam 阅读全文
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There are two approaches that can be followed when we want to deal with exceptions that occur due to unusual events: LBYL - Look Before You Leap EAFP 阅读全文
