Python Programming

So far, we have imported modules using the import statement.

import math
import random
import libmonster

You can also import multiple modules in a single line, although PEP 8 explicitly discourages this.

import math, random, libmonster

Now if you are finding it tedious to type libmonster every time you want to use a function or a class from the module, you can assign it a different name instead (for example lm). This is also useful for resolving any conflict with existing names (maybe you already have a different variable named libmonster? See line 6 for example)

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import libmonster as lm

print(lm.FACTOR)
print(lm.calculate_growthrate(2))

libmonster = 30

new_monster = lm.Monster("Crazy", "sashimi")

print(libmonster)

If you are even lazier (especially if you refer to lm a lot in the script), you can just import the functions and classes from the module directly instead. There is no need to use libmonster or lm to refer to these functions/classes in your code this way.

from libmonster import FACTOR
from libmonster import calculate_growthrate
from libmonster import Monster

print(FACTOR)
print(calculate_growthrate(2))
new_monster = Monster("Crazy", "sashimi")

PEP 8 says it is ok to import multiple variables/functions/classes in a single line.

from libmonster import FACTOR, calculate_growthrate, spawn_monsters, Monster

print(FACTOR)
print(calculate_growthrate(2))
monsters = spawn_monsters()
new_monster = Monster("Crazy", "sashimi")

Like the module names, you can also rename your variables, functions and classes when you import them.

from libmonster import calculate_growthrate as growth, Monster as Mon

print(growth(2))
new_monster = Mon("Crazy", "sashimi")

If you are super duper lazy, you can just import everything from the module.

from libmonster import *

print(FACTOR)
print(calculate_growthrate(2))
monsters = spawn_monsters()
new_monster = Monster("Crazy", "sashimi")

This will import all objects from libmonster except those that start with an underscore.

But avoid doing this unless you have a very clear reason (and laziness is not one of them!) Importing this way makes your code very difficult to read (“where did this calculate_growthrate() function come from?”). You may also end up unintentionally replacing some variables in your script with something from the module with the same name. Import only the functions or classes that you need!