```p : prints value of a variable```

```n/next : Continue execution until the next line in the current function is reached or it returns.```

```s/step : Execute the current line and stop at the first possible occasion (either in a function that is called or in the current function).```

```cont/continue : Continue execution and only stop when a breakpoint is encountered.```

```h/help : get a list of available commands```

```q/quit : exit debugging session```


Some useful commands for the Python Debugger

Starting Python 3.7 version, a built-in function ```breakpoint()``` was added to to the standard library. ```breakpoint()```can be used instead of ```import pdb; pdb.set_trace()```

Easier way to start debugging in Python 3.7

```pdb``` is a built-in python debugging tool. It is a very simple and effective tool. To start debugging session, we write the following line of code:
```python
import pdb; pdb.set_trace()
``` 
When this line is reached, python will stop the execution and start an interactive debugging session in the console.

Python 3.7 brings the ability to use breakpoint() rather than 
import pdb;pdb.set_trace()

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- General Tips & Tricks
- Common Syntax Errors
- Error types
- Error Messages

Debugging in Python

Python Documentation

- Missing comma after dictionary entry
- Confusing assignment operator (=) and comparison operator (==)
- Using Python keyword where unintended*
- Missing parentheses, brackets, or quotes**
- Adding extra parentheses or brackets
- Missing a colon at the end of a for, while, or if statement
- Improper indentation

*Note: The keyword library can be used to check if something is a Python keyword. To demonstrate,
```python
import keyword as kw
kw.iskeyword('class') # returns True
```

**Note: To initialize a string containing the quote character (e.g. English contractions), you can escape the quote symbol using a backslash:
```python
message = 'can\'t'
print(message) # prints "can't"
```

Common Syntax Errors in Python

- Look for the line number in the error message to find where the interpreter believes the error is coming from. Trace backwards if error doesn't stem from that line
- Understand the different types of errors (Syntax, Runtime, Semantic) 
- Use print statements to check the values of variables and if a block of code is being run, especially when your code has if-statements or loops
- Debug code in blocks as you go. This will make it easier to find more subtle semantic issues instead of having to look through your entire program when debugging at the end
-Usage of Break Points can be very useful if your IDE allows for it. This way you can run the program up to the break point and step through the code step by step checking the value of variables and comparing it to what you expect it to be. If there is a miss-match then you can trace it back to the line where the program deviated from your intended functionality. 

-When dealing with large amounts of data, use mocking to test your code as you build bigger projects. Mocking is the action of running smaller, more palpable data sets through code to more easily see errors in code designed for larger amounts of data. 

General Tips for Debugging

- Syntax Errors
- Semantic Errors
- Runtime Errors

Error Types

Python built-in debugger "pdb"

Python provides a construct called the try-except construct that allows a programmer to capture a runtime error and give the programmer the option to handle that error.

```python
try:
     #code
except (insert_error_name):
     #code to run when faced this error
```

Try and except blocks allows for multiple different except blocks to handle a variety of errors. Exceptions can also be raised intentionally to test try and except functionality. 

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