Super-specifically, I use By in the Python API of WebDriver, but I want to know what this declares. I remember `By.NAME```, but I wonder if it is By.CLASS_NAME``` or `` By.CLASS```.

At that time, I would do something like ``` locate'/ usr * python * webdriver * by *'` ``, which is kind of stupid.

> locate '/usr*python*/webdriver*by*'
/usr/local/lib/python2.7/dist-packages/selenium/webdriver/common/by.py
/usr/local/lib/python2.7/dist-packages/selenium/webdriver/common/by.pyc

(See in view or emacs)

I will introduce the method of ipython as a bean knowledge. Just add two?

In [1]> from selenium.webdriver.common.by import By
In [2]> By??
Type:        type
String form: <class 'selenium.webdriver.common.by.By'>
File:        /usr/local/lib/python2.7/dist-packages/selenium/webdriver/common/by.py
Source:
class By(object):
    """
    Set of supported locator strategies.
    """

    ID = "id"
    XPATH = "xpath"
    LINK_TEXT = "link text"
    PARTIAL_LINK_TEXT = "partial link text"
    NAME = "name"
    TAG_NAME = "tag name"
    CLASS_NAME = "class name"
    CSS_SELECTOR = "css selector"

    @classmethod
    def is_valid(cls, by):
        for attr in dir(cls):
            if by == getattr(cls, attr):
                return True
        return False

For some reason, there was an introductory article on ipython in the book "Introduction to Data Analysis with Python", and I thought again that it was a shame that I didn't know the tool I was using.

The iPython cheat sheet is as follows.

http://damontallen.github.io/IPython-quick-ref-sheets/

bonus

This is also from the same book, but I was shocked soberly, so for reference (python-matplotlib package etc. are required first)

> ipython --pylab
In [1]> plot(np.random.randn(100).cumsum())

See https://www.youtube.com/watch?v=BrDJssegqwo to see how it works

View the implementation source code in iPython

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