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Python - Learn Note (3)

Jul 13, 2017 pm 06:13 PM
Notepython

Python module

Package is a folder; a package can have multiple levels;

Module is the xxx.py file; you can create your own modules and import them. The name of the module is the same as the name of the file;

Python uses the import statement to import a module.

import math
print math.sqrt(16) # => 4

Only want to import certain functions of the used math module

from math import ceil, floor
print ceil(3.7) # => 4.0
print floor(3.7) # => 3.0

# Import all definitions from the module
# Warning: Deprecated
from math import *

Using from...import to import functions sometimes causes conflicts with the same name. At this time, you can give the function an "alias" to avoid conflicts ;

from math import log
from logging import log as logger   <span style="color: #b22222"># logging的log现在变成了logger
print log(10)   <span style="color: #b22222"># 调用的是math的log
logger(10, 'import from logging')   <span style="color: #b22222"># 调用的是logging的log</span></span></span>

# You can also use the dir method to check what attributes and methods are in the module
import math
dir(math)

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