[learn Python from simple to profound] four usages of import statement

One 、import … Import the whole module into

import turtle
turtle.circle(100)

Two 、from … import…

explain ：
1） Import a member in the module ;
2） It can be used * On behalf of all members , Such as from Module name import *

from pandas import Series
# Instantiation 
ser1=Series(data=[4,7,-5,3])
print(ser1.values)
print(ser1.sum())

[ 4 7 -5 3]
9

3、 ... and 、import …as … Give the module a short name

import numpy as np
print(np.pi)
# Format output {} Represents a placeholder , The results don't show , Internal parameters can be added 
print("pi value :{:.2f}".format(np.pi))

3.141592653589793
pi value :3.14

Four 、from… import * Import all functions under the module

from turtle import *
circle(100)