fix: raw string

[superlevure]

Fix for this Python warning:

DeprecationWarning: invalid escape sequence '\{'
    block_match = re.match(" \{\n(?P<field_str>.*)\n\}", str_field, flags=re.DOTALL)

[coveralls]

Pull Request Test Coverage Report for Build 3622869338

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 91.071%

---

Totals
Change from base Build 3361343288:	0.0%
Covered Lines:	204
Relevant Lines:	224

---

💛 - Coveralls

[erikwrede]

Thank you @patrick91 @superlevure 🙂 3.0.2 is on PyPi now!

[superlevure]

That was quick ! Thank you both