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shrihanacharya
6,958 PointsUsing datetime
I’m having trouble with knowing how to format date time in Python. I’m mixing up variables by doing, for example, apples.timedelta() - oranges.timedelta, instead of doing, datetime.timedelta(apples - oranges). Can someone explain when u use dot notation or when you pass something in as a parameter? Also can someone explain when you are supposed to write the date time thing twice and when you’re not supposed to?
2 Answers
Steven Parker
231,269 PointsThe dot is also known as the "membership operator". You use dot notation to access something that is part of something else, like a class within a module, or method or attribute within a class.
Arguments are only passed when calling a function or method. This would include the internal __init__ method when constructing a new object.
And datetime is the name of both a module, and a class within that module. So if you import the module, you would use both names to access the class:
import datetime
start = datetime.datetime.now()
# ^^^^^^^^ ^^^^^^^^ ^^^
# module class method
But if you import the class itself, you can reference it without naming the module:
from datetime import datetime
# ^^^^^^^^ ^^^^^^^^
# module class
start = datetime.now()
shrihanacharya
6,958 PointsThank you