Top 30 Useful Python Snippets that are Useful for Your Next Project

2 minute read

Check if a string is empty:

if not my_string:
    print("String is empty")

Sort a dictionary by value:

sorted_dict = dict(sorted(my_dict.items(), key=lambda x: x[1]))

Flatten a list of lists:

flattened_list = [item for sublist in my_list for item in sublist]

Check if a list contains duplicates:

if len(my_list) != len(set(my_list)):
    print("List contains duplicates")

Get the current date and time:

import datetime
now = datetime.datetime.now()

Get the file extension from a file path:

file_extension = os.path.splitext(file_path)[1]

Convert a string to a boolean:

my_bool = my_string.lower() in ['true', 't', 'yes', 'y', '1']

Remove duplicates from a list while preserving order

  seen = set()
  unique_list = [x for x in my_list if x not in seen and not seen.add(x)]

Convert a list of strings to a single string:
```
  my_string = ' '.join(my_list)
```

Generate a random number:

  import random
  random_number = random.randint(min_value, max_value)

Get the size of a file:

  file_size = os.path.getsize(file_path)

Replace all occurrences of a substring in a string:

  new_string = my_string.replace(substring, new_substring)

Filter a list based on a condition:

  filtered_list = [x for x in my_list if condition(x)]

Check if a file exists:

  if os.path.isfile(file_path):
      print("File exists")

Read a file line by line:

  with open(file_path) as f:
      for line in f:
          print(line)

Create a directory if it does not exist:

  if not os.path.exists(directory_path):
      os.makedirs(directory_path)

Creating a dictionary from two lists:

keys = ['a', 'b', 'c']
values = [1, 2, 3]
my_dict = dict(zip(keys, values))

Checking if a file exists:

import os
if os.path.exists('/path/to/file.txt'):
    # do something

Getting the current date and time:

from datetime import datetime
now = datetime.now()
current_time = now.strftime("%H:%M:%S")

Reversing a string:

my_string = "Hello, world!"
reversed_string = my_string[::-1]

Generating a random number:

import random
my_number = random.randint(1, 100)

Converting a string to a list:

my_string = "apple,banana,orange"
my_list = my_string.split(",")

Sorting a list of dictionaries by a specific key:

my_list = [{'name': 'John', 'age': 25}, {'name': 'Jane', 'age': 20}]
sorted_list = sorted(my_list, key=lambda x: x['age'])

Removing duplicates from a list:

my_list = [1, 2, 3, 2, 1]
my_list = list(set(my_list))

Checking if a string contains a substring:

my_string = "Hello, world!"
if "world" in my_string:
    # do something

Joining a list of strings into a single string:

  my_list = ['apple', 'banana', 'orange']
  my_string = ', '.join(my_list)

That’s all for today! Cheers!!!

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