How do you get all the methods of a class in Python?

How do you get all the methods of a class in Python?

I'd be happy to help! In Python, there are several ways to retrieve the methods (or functions) of a class. Here are a few approaches:

Method 1: Using dir()

One straightforward way is to use the built-in dir() function in Python. This function returns a list of strings that contain the names of the methods and variables defined in an object (in this case, a class). You can pass your class instance as an argument to dir(), like so:

class MyClass:
def method1(self):
pass
def method2(self):
pass
my_obj = MyClass()
print(dir(my_obj))

This will output something like:

['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__subclasses__', '__subclasshook__', '__str__', '__weakref__', 'method1', 'method2']

As you can see, the output includes not only the class methods (in this case, method1 and method2) but also various special method names that Python uses internally. You'll want to filter out these internal method names if all you're interested in are your custom-defined methods.

Method 2: Using inspect.getmembers()

Another way is to use the inspect module's getmembers() function. This function returns a list of tuples, where each tuple contains a member name (e.g., a method or variable) and its value.

Here's an example:

import inspect
class MyClass:
def method1(self):
pass
def method2(self):
pass
my_obj = MyClass()
methods = [(name, getattr(my_obj, name)) for name in dir(my_obj) if callable(getattr(my_obj, name))]
print(methods)

This will output a list of tuples, each containing the method name and its corresponding value:

[('method1', >),
('method2', <bound method MyClass.method2 of <main.MyClass object at 0x7f9e4b6c7d50>>) ...]

The getmembers() function allows you to filter out non-callable (i.e., non-method) members by using the callable function.

Method 3: Using Reflection

Another approach is to use Python's reflection capabilities through the __dict__ attribute, which provides a dictionary view of an object's attributes. Here's an example:

class MyClass:
def method1(self):
pass
def method2(self):
pass
my_obj = MyClass()
methods = [method_name for method_name in dir(my_obj.class) if callable(getattr(my_obj.class, method_name))]
print(methods)

This will also output the list of method names:

['method1', 'method2']

In this case, we're using dir() to get a list of attribute names for the class itself (my_obj.__class__), and then filtering out non-callable members as before.

There you have it! Three ways to retrieve the methods (or functions) of a class in Python.

Python class methods cheat sheet

I'd be happy to provide a cheat sheet for Python class methods!

What are Class Methods?

In Python, a class method is a static method that belongs to a class rather than an instance of the class. It's a way to associate functionality with a class, making it possible to perform certain actions without creating an object (instance) of the class.

Key Features:

Types of Class Methods:

Benefits:

Cheat Sheet:

Here are some examples and best practices for using class methods in Python:

class MyClass:
@classmethod
def my_class_method(cls):
This is a regular class method
print("This is a class method")
@staticmethod
def my_static_method():
This is a static method (no self)
print("This is a static method")

Key Takeaways:

Best Practices:

By following these guidelines, you'll be well on your way to mastering the use of class methods in Python!