The variables in the Python main function default to global variable

The variable in the main function of Python defaults to a global variable , while the other variables in the DEF function default to local variables .

Of course, local variables take precedence over global variables , as can be seen when executing formal_print (T_global) statements.

The test code is as follows:

<span style= "FONT-SIZE:18PX;" > #coding =utf-8# Test python global variables, local variable mechanism def formal_print (S_global): #常规的传参用法, pass parameters to print, variable names can be arbitrarily    print "Formal_ Print: ", S_global    return def global_print (): #无参数传递, print    print" Global_print: "directly to global variable, s_ Globaldef Global_print_para (ST): #此处虽然传递了一个参数st, but did not use    print "Global_print_para:" In the function, S_globaldef Test_global ():    stest = ' Test_global '    print "Test_global:", stest    return if __name__ = = ' __main__ ':    s_global = ' Glob Al variable s_global ' #main函数中声明的变量默认为global variable, while the variables declared in other DEF functions default to local variable    t_global = ' global variable T_global '    formal_print (s_global)    formal_print (T_global)    global_print ()    Test_global ()    # The variable stest is declared in Formal_print (stest) #虽然在test_global (), but Stest is not a global variable,        print ' End. ' </span>