This article explains step by step how to deploy a Python Flask application on an Apache WebServer on Mac. The diagram below explains how the Apache server will work with our code:

Step 1:

Install Flask:

Type this command into your terminal to install Flask on your machine:

Step 2:

Install mod_wsgi:

Type this command into your terminal to install mod_wsgi on your machine:

Step 3:

Create a Flask application:

Create a .py file for your Flask application. Let’s name it “Hello_Flask.py” . We also need to make a folder for this file(I named mine “Alaina_code”). Now enter the following code into your .py file:

Step 4:

Create a WSGI file:

In order for the Apache server to understand the code we wrote in “Hello_Flask.py”, we need to make a .wsgi file. Let’s name it “Flsk_config.wsgi”. Put this file in the folder we made in the last step and enter in the following code into it:

Step 5:

Editing and working with httpd.conf:

We finally need Apache to recognize the WSGI file we wrote. Apache’s config file(httpd.conf) should be available at this path:‘/etc/apache2’. Open it and enter in the following:

Now you should be able to run your program. To test it, type into the browser:

http://localhost/flasktest/Hello

You should be getting a message like this:

Here we take the variable ‘i’ and use it to print the sentence 5 times. As you could tell, the range factor tells the range of how many times the task would be repeated. By default, the first value in the “range” is 0, but if you want, you can change it and instead do something like the following:

When doing this, the task inside the loop will be done 3 times, since the range between 2 and 5 is 3.
For loops can also be used to, for example, read through one at a time a list of words in a list. For example:

For absolute beginners, this might look a little complicated, but whats happening hear, is that by creating this variable ‘i’ for our loop, and saying that it’s representing the values in ‘MyList’, when we come back around in our loop, every time, it moves on to the next value in the list, or adds one.

For loops are used in a variety of complicated programs, and require logic and thinking to understand them, but with practice, the concept of for loops makes for easier and on-point programs.

Another short simple tutorial about the basics of python covers the print statements. If you’re familiar with other languages, you might already know that a ‘print statement’ is a line or two of code that prints a string ( a combination of letters) or numbers in your local python console. This simple tutorial explains how this simple statement works.
A print statement is useful when you want to find information that your program is computing. The print statement is a built in Python function that starts like this:

When printing in a hardcoded string, unlike other languages, Python is pretty flexible. You’ll get the same result if you use double or single quotes.

Now lets think how to print a variable. When printing a variable, you first define it, and then put it into the parenthesis without any quotes, like this:

Finally, we will learn how to concatenate a variable and a string in a print statement. Concatenating is when you combine two different strings in a print statement like this:

Here we use the plus sign to combine these two strings. The only problem with this is that we can only combine strings. If you try to do something like this:

You would get an error.
I hope that this tutorial helped and please comment with any questions!

In this example we used the variable to store a number, however, if you want to store a string, you should surround it with quotation marks for it to be valid:

You can essentially name your variable anything you like, however it is best to name it something unique and easy to remember.
So now that we know how to define variables, now we can talk about how to actually use them in our programs. We can use variables in several different situations: we use variables to store information and be referenced to, and even manipulated in our programs. It also helps to label our information with a discriptive name so that our programs can be clean, organized and easilly understood. Here is an example on how we can use variables in a simple beginner program:

If you do the math on your own, you’ll be able to figure out that after we run this program, the computer should return this as our answer:

I hope this tutorial helped in understand Python Variables! As always, leave any questions or concerns down in the comment section.

As you can imagine, upon calling this function, (calling means to run the function which I will explain later on), it will returns (or give back) the answer 12. The parenthesis next to the name of the function is not optional and is there to hold your parameters. One way to think of parameters is as variables to use inside the function. For example, if there is a dynamic value you need to use in your program, you will set it as a parameter, then set the value of the parameter upon calling the function. For example:

Here, x and y aren’t given a value, and instead, we will define them when we call the function.
Calling a function

The above image is an example of how to call a function. In this case, we are printing the result of the function with the name and parenthesis next to it. If we have any parameters in the function, we need to define them here like so:

SYNTAX

Here as shown, if loops start with the word if, then after that enter in the hypothetical statement (Such as if my name is Alaina). If you want to put an equals to in the If like I did, make sure it’s double. At the end of the statement, put a colon as shown above. This automatically puts a tab underneath the statement which is also a must.
Another feature of if statements are the ‘else’. When you have an if statement and you want your program to choose one category or another while running, it can be helpful to add an ‘else’ after the If statement.

Here, if someone didn’t enter in their age as twelve, the code would check the if loop, and see that it didn’t satisfy the requirement for it, and then immediately fall into the “else” category.

SYNTAX

The syntax of the else is similar to that of the if; put a colon at the end and just the word else. You don’t need to specify any category because the two choices your program will have to go into is (in our case) the “is 12” category, and the “every other number that isn’t 12” category.

Finally, the last feature of the IF I’ll be talking about is the “elif”. For some people, this may be a completely new concept in any language, so let me explain.
With the previous If and else statements, you only have to cases to deal with, If a special case, and everything else, but what if we have more than two scenarios to deal with? This is when our ‘elif’ or ‘else/if’ comes into play. In this case, we will have to write something like this:

Here, instead of an automatic else, it’s almost like we’re adding another if, except it’s in the same chain of if and else.
But why can’t we just put another if? Well, when we had the if and else statement in the beginning, the if was connected to the else, so if the if statement wasn’t satisfied, it would fit into the else category, but once you start another if statement, all your code isn’t going to be as neatly connected as it can be with an elif.

SYNTAX

You can use as many elifs as you want in a program, the only rules are that they are a lot like ifs, and your sequence of them needs to start with an if, (an elif can’t stand alone, just like a train needs an engine car at the front) and ends with an else.
I hope this tutorial helped you understand the basics of if statements. Go into the comments for any questions!

In this tutorial, I’m going to be teaching you some of the most common face-recognition functions and then provide code for one of my face recognition python programs.
First we need to install face-recognition:
To install the face-recognition library on your machine, you can use the following command in the terminal:

Here are some common lines you can use in your face recognition programs and what they do:

Obviously, this line is to import the library into your program

This line tells face-recognition which picture you want it to analyze.

This line returns a list of encodings face-recognition will use to detect faces. Of course if you saved the previous line in a variable, put the name of that variable in place of “face_recognition.load_image_file(“your_file.jpg”)”

This line is for comparing to faces and returns a boolean response. If it’s true, that means that the two pictures it’s comparing are of the same person. The third parameter, is of the tolerance. Depending on how high the tolerance is, the more closely face-recognition checks for those tiny details of the face. I found that 0.5 is the perfect tolerance for most pictures. Too much or too little tolerance will cause your program to break, so I would recommend to go with 0.5. If that doesn’t work, you can experiment with different tolerances.
If you want to see some sample face-recognition applications, visit my face-recognition repository at
https://github.com/alainaahuja/face_recognition
Flask on Apache
How to Deploy a Flask Application on Apache WebServer on Mac
This article explains step by step how to deploy a Python Flask application on an Apache WebServer on Mac. The diagram below explains how the Apache server will work with our code

Install Flask:
Type this command into your terminal to install Flask on your machine:

Step 2:
Install mod_wsgi:
Type this command into your terminal to install mod_wsgi on your machine:

Step 3:
Create a Flask application:
Create a .py file for your Flask application. Let’s name it “Hello_Flask.py” . We also need to make a folder for this file(I named mine “Alaina_code”). Now enter the following code into your .py file:

Step 4:
Create a WSGI file:

In order for the Apache server to understand the code we wrote in “Hello_Flask.py”, we need to make a .wsgi file. Let’s name it “Flsk_config.wsgi”. Put this file in the folder we made in the last step and enter in the following code into it:

Step 5:
Editing and working with httpd.conf:
We finally need Apache to recognize the WSGI file we wrote. Apache’s config file(httpd.conf) should be available at this path:‘/etc/apache2’. Open it and enter in the following:

Now you should be able to run your program. To test it, type into the browser:
http://localhost/flasktest/Hello
You should be getting a message like this:

If you press “Go to Folder…” , it will give you a small window where you can type in the path of the folder you want to navigate to:

Once you click it, you should see a field to enter your skills name, your default language, The type of skill you want to create etc. For this Hello World skill, we’re going to name it “Alexa Hello”. Choose “Custom” for the skill’s model and since we’re going to be coding this skill in python, choose “Alexa-Hosted(Python)”:

Click “Create Skill at the top of the page. This should take you to choose which template you want for your skill. Since we’re not doing anything too fancy here, we’re just going to stick with “Hello World Skill”:

Finally, click “Continue with Template” at the top of the page and wait for the developer console to create your skill.
Step 3: Understanding Invocations, Intents, and Slots
After everything has loaded, you should see a page with a side panel that looks like this:

The first tab called “Invocation” when clicked on offers you a block to enter in your skills invocation name. The invocation name is the phrase your user says to start your skill.
If you expand “Interaction Model”, you’ll see a number of new tabs, but the one we’re going to focus on in this tutorial is the Intents.

Intents are classes that are each responsible for doing a specific task in the Alexa Skill. Your skill should have come with 4 built in Amazon Intents as well as a HelloWorldIntent. Later, we’ll create a new custom intent to tell the user a message.
The last feature we need to talk about are slots. Slots act like variables in an Alexa Skill. For example, if you were to make a skill to order a pizza, The user could say “I want a large plain cheese pizza” but in the intents you could define this sentence using slots for the size and topping: “I want a {size} {topping} pizza”.
Step 4: Defining in the UI
Now we’re going to start defining our invocation name and intents. First go into the “Invocation” tab and enter “hello my name” as the skill invocation name.

Next we’re going to create our own custom intent. Click the Intents tab on the side panel and click on “Add Intent”. Let’s name this intent “Greeting”.

Then you should see a space for Sample Utterances. Sample utterances are phrases the user might say to invoke the intent. For example, If you have the skill to order the pizza, and you have a PizzaOrder intent, one of the sample utterances could be “Order a pizza” and so that will tell the skill that the user wants to order a pizza so it will find the intent that will be able to complete the task.
Our skill will say hello to the user, so the user will invoke the intent by telling Alexa hello. Add the following utterances:

Now that everything is defined, for all these changes to take place, we need to build the model. Click “Build Model” at the near top of the screen and once the build is successful, you’re done building the UI part of the skill!
Step 5: Write the code
Now the build is successful, click on the tab that says code at the top of your screen. A file named ‘lambda_function.py’ should be open. And here is where you will do all the backend code for your intent. Create a new class for your intent and enter in the following code:

Scroll to the bottom of the file and add this line:

Finally press the “Deploy” button at the top of the screen and move on to the test tab(also at the top of the screen)
Step 6: Testing
Now we’re in the test tab. Just in case you don’t have an Alexa device at home, you can still create these skills, because the developer console has a built-in Alexa stimulator. To enable it, expand the drop down menu that is now set to “off” and choose development.

Now we can use our skill as if we are users. Start the skill with your invocation name, and then invoke your intent by saying hello: