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Great, we were able to build this map in
the previous lecture, so we have a base

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map and we have a marker feature here.
This is our code. Now in this lecture

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I'll show you how to add multiple
markers to your map. And the way to do

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that is to, one of the ways to do that is
to write this expression multiple times

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so like that and of course you need to
change the locations of those markers.

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Save the script and execute, reload,
and so you have multiple markers.

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As you realize it's not possible to add
multiple markers with one single method,

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so with one single marker methods.
You need to apply the method multiple.

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However this is not very smart
to do, and that's the beauty of

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programming you can use a for loop to
actually add multiple markers to the map.

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So we're talking about the Python for
loop which is one of the fundamental

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features of Python, so the for loop has
nothing to do with Folium. Let's say

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for coordinates in, of course you'd
need some sort of input with the

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coordinates. I don't know let's say like
that, let's say a list of lists, so we

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have these two coordinates. Let me copy
this, put it there, another time. and let

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me change them to nine and seven and
then you need to indent this with four

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white spaces. I'll explain this
in just a bit.

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Then in location you'd need to pass coordinates.
Before explaining the code to you, let me

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try this out. Execute, go to reload and yeha,
we still have the markers there. Of course the

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location changed from the previous one
because I changed the coordinates in here.

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So how is this working?
Well I'm iterating with a for loop

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through this list of lists, so the items
of these lists, of this main list are

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two other lists, so the items can be
anything, in this case there are two lists.

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So what happens is that the
coordinates variable in the first

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iteration it will get to this first item
of the list, and it will put that small

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list so 32.2 minus 99.1, it will put
that list in here, and so

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basically this will be put in here.
More or less. That's the idea.

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And then in the next iteration, coordinates
will fetch this other list and it

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will put it in here again, and so the
marker method will be executed two times.

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And so the first time it will generate a
marker with these coordinate, and then the

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second iteration it will
generate a marker with these coordinates.

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And that's it. However we have a small
issue here, and the issue is that you know

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in reality you cannot just type the
coordinate in a Python list. Let's say

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you have a thousand coordinator that
you need to map into a map, and you can,

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and it's hard to type them in here,
or even paste them, copy and paste

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them from a document in here, so the
solution to that is that your

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coordinates normal in real life
come as maybe a text file like a comma

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separated text file, CSV, Excel files etc.
You want to load that file into Python

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and then you want to add the values of
that file into the marker method and

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you can do that using a for loop and
how you do that exactly? Well I'll explain

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that in the next lecture where I'll give
you a comma-separated file with lots of

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coordinates, and we're going to use that
in this script so I'll talk to you later.