python

Dependency injection is a design pattern commonly used in software engineering that allows for the separation of concerns and promotes code reusability. It is a technique that enables the creation of loosely coupled code, which can be easily tested, maintained, and extended. What is Dependency Injection? Dependency injection is a design pattern that allows for the separation of concerns between different parts of a program or system. In dependency injection, the dependencies required by a component or module are injected into it at runtime, rather than being hardcoded into the component or module....

In Python, a singleton is a design pattern that restricts the instantiation of a class to a single object. A singleton class ensures that only one instance of the class is created and provides a global point of access to that instance. One way to implement a singleton in Python is to use a decorator. Here’s an example: def singleton(cls): instances = {} def get_instance(*args, **kwargs): if cls not in instances: instances[cls] = cls(*args, **kwargs) return instances[cls] return get_instance @singleton class MyClass: def __init__(self, x): self....

In Python, there are several types of comprehensions that can be used to create new data structures from existing ones: list comprehension A list comprehension is a concise way to create a new list by iterating over an existing iterable and applying a transformation or filtering condition to each element. Here’s an example: my_list = [1, 2, 3, 4, 5] squared_list = [x*x for x in my_list] print(squared_list) # Output: [1, 4, 9, 16, 25] In this example, the list comprehension [x*x for x in my_list] creates a new list by squaring each element of my_list....

In Python, there are several ways to pass arguments to a function, including positional arguments, keyword arguments, default arguments, variable-length argument lists (*args), and variable-length keyword argument dictionaries (**kwargs). The choice of argument passing method depends on the specific requirements of the function and the nature of the data being passed. Here’s a brief overview of the different argument passing methods in Python: Positional arguments: Positional arguments are passed to a function based on their position in the argument list....

In Python, an array is a data structure that stores a collection of elements of the same data type. Unlike lists, which can contain elements of different data types, arrays can only contain elements of a single data type, such as integers, floats, or characters. Python supports two types of arrays: arrays provided by the built-in array module and arrays provided by the numpy module. built-in array module The array module provides a simple way to create and manipulate arrays of primitive data types, such as integers, floats, and characters....