Writing Unicode-aware Programs

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You know, that ***** thing that makes your code look like a bunch of gibberish when you try to display non-ASCII characters?

First what is Unicode anyway? It’s a standard that allows us to represent text using characters from pretty much any language or script. This means we can finally say goodbye to those ***** “not supported” errors when trying to display foreign languages on our screens!

With Python 3 (and later), Unicode is the default encoding for strings. That’s right no more messing around with `utf-8` or `latin-1`. Just write your code as you normally would and let Python handle the rest.

Now that we have a basic understanding of what Unicode is, Let’s get started with some tips for writing Unicode-aware programs:

1) Always use raw strings when working with non-ASCII characters. This will prevent any potential encoding issues caused by escaping special characters like backslashes or quotes. For example:

# This script prints "世界!" in Japanese using raw strings to avoid encoding issues.

# Import the necessary module for working with Unicode characters
import sys

# Set the default encoding to UTF-8 to ensure proper handling of Unicode characters
sys.setdefaultencoding('UTF8')

# Define a raw string using the 'r' prefix to prevent escaping of special characters
message = r"世界！"


print(message)

2) Use the `unicodedata` module to access Unicode data, such as character properties and code points. This can be useful for tasks like checking if a given string contains only ASCII characters or converting between different encodings:

# Import the unicodedata module to access Unicode data
import unicodedata

# Define a string with non-ASCII characters
string = "世界！"

# Check if all characters in the string are ASCII characters
# The `all()` function checks if all elements in a given iterable are True
# The `in` operator checks if a given character is present in a given string
# The `ascii_letters` and `digits` variables contain all ASCII letters and digits respectively
if all(c in ascii_letters + digits for c in string):
    # If all characters are ASCII, print a message
    print("This is an ASCII-only string")
else:
    # If any character is non-ASCII, print a message
    print("This contains non-ASCII characters")

3) Use the `codecs` module to convert between different encodings. This can be useful when working with legacy systems or dealing with data that has been corrupted during transmission:

# Import the codecs module to convert between different encodings
import codecs

# Open the input file in read mode and assign it to the variable 'f'
with open('input_file.txt', 'r') as f:
    # Read the contents of the file and assign it to the variable 'text'
    text = f.read()
    
    # Convert the text from UTF-16 to UTF-8 (assuming little-endian) using the codecs module
    # First, decode the text from UTF-16 to unicode using the decode() function
    # Then, encode the decoded text to UTF-8 using the encode() function
    output_text = codecs.encode(codecs.decode(text, 'utf-16'), 'utf-8')

4) Use the `re` module for pattern matching with Unicode characters. This can be useful when working with text data that contains non-ASCII characters:

# Import the re module for pattern matching with Unicode characters
import re

# Define a string containing non-ASCII characters
string = "世界！"

# Use the re.search() function to search for a pattern within the string
# The r prefix indicates a raw string, which is used for regular expressions
# The [] brackets indicate a character set, which will match any character within it
# In this case, we want to match any Japanese vowel, so we use the character set [あいうえお]
# Note: This is not a comprehensive list of Japanese vowels, but it serves as an example
match = re.search(r'[あいうえお]', string)

# Check if a match was found
if match:
    # If a match was found, print a message indicating a Japanese vowel was found
    print("Found a Japanese vowel!")
else:
    # If no match was found, print a message indicating no Japanese vowels were found
    print("No Japanese vowels found.")

And there you have it some tips for writing Unicode-aware programs with Python. Remember, always use raw strings when working with non-ASCII characters and be careful when converting between different encodings.

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