module & packages Flashcards
What is a Python module?
A Python module is a file containing Python code, such as functions, classes, and variables, that can be imported into other scripts.
How do you import a module in Python?
Using the import statement:
```python
import module_name
~~~
What are the three types of Python modules?
- Built-in modules (e.g., os, sys)
- Third-party modules (installed via pip)
- User-defined modules (custom .py files)
How is a Python module different from a JavaScript module?
Python modules use import, while JavaScript ES6 modules use import/export, and CommonJS uses require().
How do you import a specific function from a module?
Using:
```python
from module_name import function_name
~~~
Why is from module import * considered bad practice?
It makes the code harder to read and can cause naming conflicts.
How do you access functions from an imported module?
Use dot notation:
```python
import module_name
module_name.function_name()
~~~
What happens if Python can’t find the module you are trying to import?
It raises an ImportError exception.
In what order does Python search for a module?
- Current directory
- PYTHONPATH environment variable
- Standard library directories
What is a Python package?
A collection of multiple modules organized in a directory with an __init__.py file.
How is a Python package different from a module?
A package is a directory containing multiple modules, while a module is a single file.
What is __init__.py used for in a package?
It marks a directory as a package and can contain initialization code.
Can __init__.py be empty?
Yes, it just needs to exist for the directory to be recognized as a package.
How do you import a module from a package?
Using:
```python
from package_name import module_name
~~~
How can __init__.py simplify imports?
By importing submodules inside it:
```python
from .module1 import function1
~~~
What happens when a module is imported?
The Python interpreter executes the module’s code in an isolated scope.
How does Python prevent modules from polluting the global namespace?
Imported modules are stored in their own namespace, avoiding conflicts.
How do you check where a module is located?
Using:
```python
import module_name
print(module_name.__file__)
~~~
What is the recommended way to name a module?
Use short, lowercase names without special symbols.
How does Python handle cyclic imports?
It partially loads modules to avoid infinite loops but can still cause issues.
