How to Fix - SyntaxError: (Unicode Error) 'Unicodeescape' Codec Can't Decode Bytes

Encountering Unicode errors is not uncommon, especially when dealing with strings containing escape sequences. One such error, "Unicode Error: 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape," can be perplexing for beginners. In this article, we will see what is SyntaxError: (Unicode Error) 'Unicodeescape' Codec Can't Decode Bytes error and how to fix it.

What is SyntaxError: (Unicode Error) 'Unicodeescape' Codec Can't Decode Bytes in Python?

The "Unicode Error: 'unicodeescape' codec can't decode bytes" occurs when Python's Unicode decoder encounters an invalid Unicode escape sequence in a string. The specific error message "truncated \UXXXXXXXX escape" indicates that the escape sequence is incomplete or truncated.

Error Syntax

SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape

Below are the reasons to which SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape occurs in Python:

1. Invalid Escape Sequences
2. Truncated Escape Sequences

Invalid Escape Sequences

In this code, a file path is assigned to the variable file_path, but the backslashes in the Windows file path should be escaped to avoid interpreting them as escape sequences. Using backslashes in strings without properly escaping them or forming valid Unicode escape sequences can trigger this error.

# Problematic code with an invalid escape sequence
file_path = "C:\Users\User\Documents\data.txt"

Output:

Hangup (SIGHUP)
File "Solution.py", line 2
file_path = "C:\Users\User\Documents\data.txt"
^
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape

Truncated Escape Sequences

In this code, the file path assigned to file_path contains a truncated escape sequence (\U) which might lead to unexpected behavior or errors.

# Problematic code with a truncated escape sequence
file_path = "C:\Users\User\Documents\data\U1234.txt"

Output:

Hangup (SIGHUP)
File "Solution.py", line 2
file_path = "C:\Users\User\Documents\data\U1234.txt"
^
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape

Solution for SyntaxError: (Unicode Error) 'Unicodeescape' Codec Can't Decode Bytes

If you encounter this error, it usually means Python is interpreting backslashes (\) in your string as escape sequences. Here are reliable ways to fix it:

1. Use Raw Strings: Utilize raw strings by prefixing string literals with 'r', which treats backslashes as literal characters and prevents Python from interpreting them as escape sequences.

file_path = r"C:\Users\User\Documents\data.txt"
print(file_path)

C:\Users\User\Documents\data.txt

2. Double Backslashes: Escape backslashes by doubling them (\), explicitly indicating that they should be treated as literal characters.

file_path = "C:\\Users\\User\\Documents\\data.txt"
print(file_path)

C:\Users\User\Documents\data.txt

3. Use Forward Slashes: Python also accepts forward slashes / in file paths on Windows, avoiding escape issues entirely:

file_path = "C:/Users/User/Documents/data.txt"
print(file_path)

C:/Users/User/Documents/data.txt

4. Ensure Complete Unicode Escape Sequences: If you intentionally use \U (Unicode escape), make sure it has exactly 8 hexadecimal digits:

file_path = "C:\\Users\\User\\Documents\\data\\U12345678.txt"
print(file_path)

C:\Users\User\Documents\data\U12345678.txt

5. Use pathlib for Safer Paths: For cross-platform safety and to avoid manual escaping, use Python’s pathlib:

from pathlib import Path
file_path = Path("C:/Users/User/Documents/data.txt")
print(file_path)

C:/Users/User/Documents/data.txt

Tips:

• Avoid copy-pasting paths directly from Windows Explorer; hidden characters can cause errors.
• Check for accidental \U in your path it is interpreted as a Unicode escape.
• Using pathlib or forward slashes is usually the safest option.