file = r'resources\views\public-test\fill.blade.php'
with open(file, 'r', encoding='utf-8') as f:
    c = f.read()

old = '<form method="POST" action="{{ route(\'public-test.submit\', $participant->token) }}">'
new = '<form method="POST" action="{{ route(\'public-test.submit\', $participant->token) }}" novalidate>'

if old in c:
    c = c.replace(old, new)
    print("OK!")
else:
    print("GAGAL")

with open(file, 'w', encoding='utf-8') as f:
    f.write(c)