10 Python built-in functions you should know

As a flexible and powerful programming language, Python has conquered the hearts of programmers, data experts and software craftsmen around the world. Python's massive adoption stems from its rich set of native commands that simplify complex processes, shorten development time, and improve script readability. In this article, we will take an in-depth look at ten key Python native commands that every programmer needs to master for a seamless and efficient coding journey.

Use len() function

len() command is a simple yet indispensable mechanism for determining the size (i.e., the count of components) of a specified iterable object such as a list, tuple, or string.

Example

expression = "Python"
size = len(expression)
print(size)

Output

6

Use sum()

sum() command provides the sum of all components in an iterable object. Use this command to avoid writing a loop to calculate the sum of a list or tuple.

Example

digits = [1, 2, 3, 4, 5]
aggregate = sum(digits)
print(aggregate)

Output

15

Use map() function

The map() command implements a specific function on all components in an iterable object (e.g., list, tuple) and generates an iterator. This command is useful when you need to use a specific function to manipulate each component in the collection.

Example

def square(y):
   return y * y
digits = [1, 2, 3, 4, 5]
squared_digits = map(square, digits)
print(list(squared_digits))

Output

[1, 4, 9, 16, 25]

Use filter()

The filter() command separates components from an iterable object based on predetermined conditions. It accepts two parameters: a function used to define the filter conditions and an iterable object used to filter. The result is an iterator containing elements that satisfy the condition.

Example

def is_even(y):
   return y % 2 == 0
digits = [1, 2, 3, 4, 5]
even_digits = filter(is_even, digits)
print(list(even_digits))

Output

[2, 4]

Use zip()

The zip() command combines two or more iterable objects together to generate an iterator of tuples, in which the first elements of each iterable object are mixed together, and then the Subsequent elements are matched together, and so on. This command is particularly useful when you need to combine data from different sources.

Example

identities = ['Alice', 'Bob', 'Charlie']
years = [25, 30, 35]
merged_data = zip(identities, years)
print(list(merged_data))

Output

[('Alice', 25), ('Bob', 30), ('Charlie', 35)]

Use sorted()

The sorted() command generates a new sorted list from the specified iterable object. By default, it sorts components in ascending order. The sorting method can be adjusted by using the optional "key" and "reverse" parameters.

Example

digits = [5, 2, 1, 4, 3]
sorted_digits = sorted(digits)
print(sorted_digits)

Output

[1, 2, 3, 4, 5]

Use any() and all()

any() command returns True if at least one component of the iterable object is true, otherwise it returns False. In contrast, the all() command returns True if all elements of the iterable object are true, otherwise it returns False. These commands are useful when you need to evaluate multiple conditions in a collection.

Example

list1 = [True, False, True]
list2 = [True, True, True]
print(any(list1)) 
print(all(list1)) 
print(all(list2))

Output

True
False
True

Use enumerate()

The enumerate() command is used to include a counter in an iterable object and return an enumeration object. It accepts two parameters: an iterable object and an optional 'start' value as a counter. This command becomes particularly valuable when the index and the value of the element are needed in a loop.

Example

fruit_types = ['apple', 'banana', 'cherry']
for count, value in enumerate(fruit_types, start=1):
   print(f"{count}. {value}") 

Output

1. apple
2. banana
3. cherry

Use the range() function

The range() command generates a range of numbers, often used in a loop to repeat a specific number. One, two or three parameters can be recognized, namely "start" (optional), "stop" and "step" (optional). The default values ​​of start and step are set to 0 and 1 respectively.

Example

for i in range(5):
   print(i)
for i in range(1, 5, 2):
   print(i)

Output

0
1
2
3
4
1
3

Use isinstance()

The isinstance() command is used to confirm whether the given question is an instance or subclass of the specified course. Returns True if the object is an instance or subclass of this class, False otherwise. This command is useful when you need to validate input data types or handle multiple types of inputs within a function.

Example

numeral = 5
outcome = isinstance(numeral, int)
print(outcome)
expression = 'Python'
outcome = isinstance(expression, int)
print(outcome)

Output

True
False

in conclusion

Python’s native commands are essential tools for programmers, enabling them to write concise, efficient and readable scripts. The ten commands introduced in this article are not an exhaustive list, but they represent a solid foundation upon which any programmer can build. By mastering these commands and exploring other native Python tools, you'll become proficient in solving a variety of coding challenges.

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