python入门1

import keyword

print(keyword.kwlist)

['False', 'None', 'True', 'and', 'as', 'assert', 'break', 'class', 'continue', 'def',
'del', 'elif', 'else', 'except', 'finally', 'for', 'from', 'global', 'if', 'import', 'in', 
'is', 'lambda', 'nonlocal', 'not', 'or', 'pass', 'raise', 'return', 'try', 'while', 
'with', 'yield']

as
assert

from
global
in
is
lambda
nonlocal
pass
with
yield


import  def del class  
return
while continue  break  for  if elif else  

and  or   not

False  None  True

try   except    finally   raise

mystr = input("请输入数据")
print(mystr)

import os
cmd = input("cmd:")
os.system(cmd)

name='yasepix'
print(type(name))
print(id(name))

num=111
print(type(num))
num=11111111111111111111111111111111111111111111111
print(type(num))


结果为：
<class 'int'>
<class 'int'>

R=input("r:")
print(R)
print(type(R))
R=eval(R)
print(type(R))
print(R*R*3.14159265357979)

############################
r:2
2
<class 'str'>
<class 'int'>
12.56637061431916