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shell What I have here is a Python shell, and I'm going to just show you some simple examples of how we start building expressions.
好，这是一个Python的，我会给大家看一些,关于写表达式的简单的例子。
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Python You can pick up another language in a week, couple of weeks at most, once you know how to do Python.
只要学会了，你可以在一周之内学会任意一种语言，最多两周。
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Strings are captured in Python with an open quote and some sequence of characters followed by a closed quote.
字符串在Python中,是以一个开引号开始,然后后面是一系列的字符,以一个尾引号结束。
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This is a keyword to Python that says, when it reads this in the file, it says, I'm creating a definition.
这是Python语言的关键词，当你在文件中读到这个词的时候，它的意思就是我正在创建一个定义。
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Which is, and we're going to do some examples of this, initially we just typed in expressions Python into the interpreter; that is,directly into Python And as I suggested last time, the interpreter is actually a program inside of the machine that is basically following the rules we're describing here to deduce the value and print it up.
也就是，我们将会对这一点讲解一些例子，一开始我们只是简单的把表达式输入,到解释器里面去，也就是直接传给,我上次跟大家讲过，解释器实际上是,机器内置的,按照我们描述的规则,来推算出结果值并把值显示出来的一个东西。
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Later in the term, we'll see why we have this syntax and why it wasn't just a totally arbitrary Python brain-dead decision by the designers of Python, and many languages before Python, but in fact is a pretty sensible thing.
这个学期的晚些时候,我们会去学学我们学这些语法的原因,以及这些语法其实并不是,和以前其他语言的设计者，一拍脑子做出的决定，实际上制定这些语法其实是相当明智的。
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Well, basically because it was a design choice when the creators of Python decided to create the language, they basically said, we're always going to have an explicit pointer to the instance.
好，基本上来说这是因为,这是当Python的创造者,决定创造这门语言的时候,的一个设计决定，他们主要的说了说，我们要有一个明确的,指向实例的指针。
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OK. In order to talk about Python and languages, I want to do one last thing to set the stage for what we're going to do here, and that's to talk about the different dimensions of a language.
好，为了谈论Python语言以及其他，我想做,最后一点儿准备，那就是讨论一种语言的,不同维度。
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Associated with every data type in Python is a type, which identifies the kind of thing it is.
在Python中每种类型都对应着一种数据类型，类型确定了对象的种类。
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These are instances of a class, and associated with that class are a set of methods things that I can deal with.
但是Python的基本思想是相同的，这是一些一个类的实例,这个类关联了一个方法集,我可以做的一些操作。
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Most of the time, we're going to be doing expressions inside of some piece of code, inside of a script, which is the Python word for program.
大多数情况下，我们会在一些代码内部,写一些表达式，在一个脚本里面，也就是Python里面对程序的另一种叫法。
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All right. If that sounds like a really long preamble, it is. Let's start with Python.
好，如果上面听起来像一个很长的序文，他确实是，让我们从Python开始。
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That's the Python saying, that is a command, that is a specific command to get the value of the expression and print it back out.
这代表着Python告诉我们这是一个命令，这是一个,得到表达式的值,并显示的特殊命令。
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Because in doing that, Python would then have a value that it could pass on into some other part of a computation, and if it wasn't what I wanted, I might be a long ways downstream in the computation before I actually hit some result that makes no sense.
因为如果这样做的话，Python会将,输入的值传递到下面的,一些运算中去，如果这个值的类型不是我想要的，我可能会在得到,一个毫无意义的结果之前,经历一个很长时间的,计算过程。
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In Python, it'll find it, I think one bug at a time, right John?
在Python中，它会找到它的，我觉得一回能找一个漏洞，对么John？
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Well, I call class just like a function, and you can see that below.
也就是pass了，在python中它的意思就是说。
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This is a mistake I make all the time in Python.
在编写Python语言的时候我总是犯这个错误。
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OK, you've actually seen exceptions a lot, you just didn't know that's what they were, because exceptions show up everywhere in Python. Let me give you a couple of examples.
好的，你们实际以及看过很多异常了，你就是不知道这些是什么，因为异常在Python中随处可见,我给你举些例子。
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Which is really a shame.
很不幸，Python没有提供这个功能。
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