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In this lesson, I want to talk to you about the Python datetime module.

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This is a really useful module that helps us work with dates and time.

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Going back to our day 32 start project,

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I'm going to comment out everything that's there.

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And then I'm going to import our datetime module. Now, again,

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this is the module that comes preloaded with Python

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so you don't have to install it. Now,

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one of the most useful things to get with daytime is the current date and time.

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And you can write Python code to get that from the computer. Inside this date

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time module,

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there is a class called datetime as denoted by the c here.

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And this is how you get to that class. So to get to that class,

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you tap into the datetime module

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and then you get to the datetime class.

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Now this is really confusing.

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So I prefer to rename the datetime module and give it a as so we can shorten it

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to just dt.

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And that way we can say dt.datetime

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and that looks a little bit more easier to understand than before. Nnow,

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inside this datetime class, there is a method called now,

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and this gets you the current date and time.

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So if we save this into a variable called now, and we go ahead and print

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now, then when I run this code,

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you can see it prints a very long string showing you the current year, month,

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day,

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as well as time in my local time zone with a high degree of accuracy

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here. 

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Working with that particular string is not very easy.

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If you wanted to check something like if now is the year 2020,

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then you can't really do that with just a string like that.

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That's why once you've gotten the

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now object out of this method because this method of course returns and it gets

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saved inside here, then we can tap into some of its attributes.

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So for example, we can tap into the year.

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So let's save that has the year. And if I print that, you can see

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it just gives us the year as a number.

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And if I do a type check on that,

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you can see that it has a class of integer

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whereas if I do a type check on now

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it has a class of a datetime object.

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So this way, if we managed to get hold of the year as a number,

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then we can say something like, well,

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if the current year is equal to 2020,

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then we will print something like,

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and because this rings out as true, then that gets printed out.

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In addition to the year, we've also got month, day,

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hour, minutes. So you can basically tap into anything in that date

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time string as you need. So when you write 'now.'

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you can see that there's the year, day, month, hour, minutes,

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microsecond, second,

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and you can get to the specific part of that datetime that you need.

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You can even call other methods like weekday. For example,

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if we want to know which day of the week it is, so Monday, Tuesday, Wednesday,

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then we can simply tap into now and call this weekday method.

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And now if we print out this day of the week,

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you can see that it gives us a number.

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So it remember that computers start counting from zero so 1

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means that its actually the second day of the week, which is Tuesday

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as you can see up here.

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So we've seen how we can get hold of the current day, year,

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month and whichever property you're interested in for today.

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But what if we wanted to create a daytime object of our own setting it to a

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particular date of our choosing? Well,

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let's say that I wanted to create a object that stored my date of birth.

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Well then I would tap into the dt module and create a new datetime object

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from that class. Now I get to specify, well,

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what is the year? What is the month?

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What is the day?

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And I can even go even more specific like which hour was I born in?

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And you'll notice that in here, when you look at the parameters,

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the year requires an integer,

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the month requires an interger and the day requires an integer.

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But after the hour we've got this ... as does the minute and the second

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and this is because they have default values. So if I delete this,

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the only things I'm required to give when I'm creating a new datetime object is

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the year, month and day.

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Let's say that I was born in 1995 and I was born in December the 15th.

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All right.

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Now,

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if I print this date of birth object you can see that we get 1995,

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12, 15,

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and the time in hour, minute and second are set to the default values of zero.

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If I wanted to be more specific and I wanted to set my hour of birth,

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let's say I was born at 4:00 AM,

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then we can set the hour and that updates that default value.

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So now we've seen how we can tap into the current date time and also create any

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datetime object from scratch

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then it's time to put this into practice and use it in our project.