W605.md

Pattern: Use of invalid escape sequence

Issue: -

Description

As of Python 3.6, a backslash-character pair that is not a valid escape sequence now generates a DeprecationWarning. This will eventually become a SyntaxError.

Example of incorrect code:

regex = '\.png$'

Example of correct code:

regex = r'\.png$'

Further Reading

• https://docs.python.org/3/reference/lexical_analysis.html#string-and-bytes-literals
• https://docs.python.org/3/whatsnew/3.6.html#deprecated-python-behavior