<s>[INST] <<SYS>>
You are an expert in regular expressions (regex)
<</SYS>>

Find a regex pattern that matches the following string:
1998$2F04$2F28T06%5F49%5F04.647 [/INST] pattern:
\d{4}\$2F\d{2}\$2F\d{2}T\d{2}%5F\d{2}%5F\d{2}\.\d{3} </s>