Head First Python Learning notes (others)

I. Scope of processing

(1) Python allows you to access and read the value of a global variable in a function, but it cannot be modified. To access and modify a global variable, you must explicitly indicate your intention (see Code 1), otherwise you will throw a unboundlocalerror (the local variable is not assigned to the value of the reference) (see Code 2).

#Code 1Name="Python"defwhat_happens_here ():Print(name)GlobalName Name=name+"is fantacy!"    Print(name) what_happens_here ()Print(name)#Code 2Name="Python"defwhat_happens_here ():Print(name) name=name+"is fantacy!"    Print(name) what_happens_here ()Print(name)

II. testing framework provided by Python

(1) UnitTest module

(2) Doctest module

Third, other

(1) Object Relational Tool (ORM), NoSQL, can avoid SQL

(2) Web framework: Diango,zope,turbogears,web2py,pylons

(3) GUI programming: TKINTER,PYGTK,PYKDE,WXPYTHON,PYQT

(4) Multithreading: Python is implemented using a technique called Global interpreter lock (interpreter Lock,gil). Limits python to run only in one interpreter process and cannot take advantage of multicore/processors. See more http://www.zhihu.com/question/21219976

Head First Python Learning notes (others)