Python get properties of object
I think it's worth showing the difference between the various options mentioned - often a picture is worth a thousand words. Show
To summarize:
So my common-sense approach is typically to use Note that, to keep things cleaner, I did not include In this tutorial, you’ll learn how to use Python to print an object’s attributes. Diving into the exciting world of object-oriented programming can seem an overwhelming task, when you’re just getting started with Python. Knowing how to access an object’s attributes, and be able to print all the attributes of a Python object, is an important skill to help you investigate your Python objects and, perhaps, even do a little bit of troubleshooting. We’ll close the tutorial off by
learning how to print out the attributes in a prettier format, using the Let’s take a look at what you’ll learn! The Quick Answer: Use the dir() Function
What are Python Objects?Python is an object-oriented language – because of this, much of everything in Python is an object. In order to create objects, we create classes, which are blueprints for objects. These classes define what attributes an object can have and what methods an object can have, i.e., what it can do. Let’s create a fairly simple Python class that we can use throughout this tutorial. We’ll create a Let’s get started! class Dog: def __init__(self, name, age, puppies): self.name = name self.age = age self.puppies = puppies def birthday(self): self.age += 1 def have_puppies(self, number_puppies): self.have_puppies += number_puppies What we’ve done here, is created our Let’s now create an instance of this object: teddy = Dog(name='Teddy', age=3, puppies=0) We now have a Python object of the class In this section, you’ll learn how to access a Python object’s attributes. Based on the class definition above, we know that the object has some instance attributes – specifically, name, age, and puppies. We can access an object’s instance attribute by suffixing the name of the attribute to the object. Let’s print out teddy’s age: print(teddy.name) # Returns: Teddy There may, however, be times when you want to see all the attributes available in an object. In the next two sections, you’ll learn how to find all the attributes of a Python object. Use Python’s dir to Print an Object’s AttributesOne of the easiest ways to access a Python object’s attributes is the Let’s take a look at how this function works: # Printing an object's attributes using the dir() function attributes = dir(teddy) # Returns: # ['__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__', '__str__', '__subclasshook__', '__weakref__', 'age', 'birthday', 'have_puppies', 'name', 'puppies'] We can see here that this prints out of all the attributes of a Python object, including the ones that are defined in the class definition. The Let’s take a look at the Check out some other Python tutorials on datagy, including our complete guide to styling Pandas and our comprehensive overview of Pivot Tables in Pandas! Use Python’s vars() to Print an Object’s AttributesThe
Let’s see how this works: print(vars(teddy)) # Same as print(teddy.__dict__) # Returns: # {'name': 'Teddy', 'age': 3, 'puppies': 0} We can see from the above code that we’ve returned a dictionary of the instance attributes of our object The way that this works is actually by accessing the We can also call this method on the class definition itself. Let’s see how that’s different from calling it on an object: print(vars(Dog)) # Returns # {'__module__': '__main__', '__init__': We can see here that this actually returns significantly more than just calling the function on an object instance. The dictionary also includes all the methods found within the class, as well as the other attributes provided by the If we wanted to print this out prettier, we could use the pretty
print import pprint pprint.pprint(vars(Dog)) # Returns: # {'__dict__': You’ve now learned how to print out all the attributes of a Python object in a more pretty format! ConclusionIn this post, you learned how to print out the attributes of a Python object. You learned how to create a simple Python class and how to create an object. Then, you learned how to print out all the attributes of a Python object by using the To learn more about the How do I see properties of an object in Python?dir() To list all the attributes of an object, use the built-in dir() function. It returns a long list of attribute names, that is, method and variable names of the object. There is a bunch of automatically generated attributes in any Python class.
How do you print all the properties of an object in Python?Use Python's vars() to Print an Object's Attributes
The dir() function, as shown above, prints all of the attributes of a Python object. Let's say you only wanted to print the object's instance attributes as well as their values, we can use the vars() function.
What is Property () in Python?In Python, property() is a built-in function that creates and returns a property object. The syntax of this function is: property(fget=None, fset=None, fdel=None, doc=None)
What is __ repr __ in Python?Python __repr__() function returns the object representation in string format. This method is called when repr() function is invoked on the object. If possible, the string returned should be a valid Python expression that can be used to reconstruct the object again.
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