Python Tip: How to Know If You're Importing a Class or a Module?

 When you're writing Python code, you’ve probably seen this kind of line:

from sentence_transformers import CrossEncoder

And maybe you wondered:

💭 “Is CrossEncoder a class? Or is it a module? Or... something else?”

This might seem like a small detail, but it’s actually very helpful to know what exactly you're importing, especially when you're trying to use it correctly in your code.

Let’s break it down in a simple way that anyone can understand — even if you’re just starting with Python.

🧠 First, What’s the Difference Between a Class, Module, and Function?

Let’s take a quick look at the common Python terms:

Term	What It Is	Simple Example
Module	A .py file containing code (functions, classes, variables)	math, os, random
Class	A blueprint to create objects with functions and variables	str, list, datetime
Function	A reusable block of code that does something	print(), len(), sqrt()

So when you write:

from math import sqrt

You’re importing the sqrt function from the math module.

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🔍 How to Find Out What You're Importing

Now, back to the mystery:

How do you know if you’re importing a class, module, or function?

Let’s go through 5 simple and fun ways to figure it out!

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✅ 1. Use type() to Peek Behind the Scenes

Let’s try it in a Python script or the interactive shell:

from sentence_transformers import CrossEncoder print(type(CrossEncoder))

Possible Results:

• ✅ <class 'type'> → It’s a class
  
  

• ✅ <class 'module'> → It’s a module
  
  

• ✅ <class 'function'> → It’s a function
  
  

🧪 Try it yourself:

from math import sqrt print(type(sqrt))  # Output: <class 'builtin_function_or_method'> from datetime import datetime print(type(datetime))  # Output: <class 'type'>

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✅ 2. Use the inspect Module (Superpower Tool!)

Python has a built-in module called inspect that helps you examine your code like a detective.

import inspect from sentence_transformers import CrossEncoder print(inspect.isclass(CrossEncoder))   # True if it's a class print(inspect.ismodule(CrossEncoder))  # True if it's a module print(inspect.isfunction(CrossEncoder))  # True if it's a function

Try it with other libraries like os, datetime, or even your own code!

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✅ 3. Hover or Ctrl+Click in Your IDE (Visual Shortcut)

If you use an editor like VS Code or PyCharm, just:

• Hover your mouse over the imported name, or
  
  

• Ctrl + Click (or Command + Click on Mac)
  
  

You’ll instantly see a small tooltip like:

class CrossEncoder(...)

Or:

module my_utils

It’s a fast way to check what you’re dealing with.

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✅ 4. Use the help() Function

Want to see all the juicy details about something you imported? Use help():

from datetime import datetime help(datetime)

You’ll get a full description — class name, methods, usage, and more.

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✅ 5. Check the Official Docs or GitHub

If you’re still not sure, you can Google the name or check it on:

• 📘 https://pypi.org
  
  

• 🧪 https://github.com
  
  

• 📚 https://docs.python.org
  
  

Search for class CrossEncoder or module some_module.

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📦 Real-Life Example: from sentence_transformers import CrossEncoder

Let’s look at this again:

from sentence_transformers import CrossEncoder

Now that we’re Python detectives, we can check:

from sentence_transformers import CrossEncoder print(type(CrossEncoder))

Output:

<class 'type'>

🎉 So CrossEncoder is a class. You can now use it like:

model = CrossEncoder("cross-encoder/ms-marco-MiniLM-L6-v2")

This creates an instance of the CrossEncoder class — commonly used to re-rank search results based on relevance.

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🧠 Summary – Your 5 Ways to Know What You’re Importing

Method	What To Do
type(obj)	Quick check to see class/module/function
inspect.isclass()	Check if it’s a class
Hover / Ctrl+Click	Use IDE to jump to definition
help(obj)	Get detailed documentation
Check Docs / GitHub	Confirm from source or online docs

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🎯 Final Thoughts

Python is beginner-friendly, but sometimes these small things (like "What did I just import?") can trip you up. With these tricks, you’ll never be confused again.

And the next time you use:

from xyz import abc

You’ll proudly say:

“Ah yes, abc is a class! Let me use it properly.”