syntax_data: {"ast_node_type":"other","tokens":[{"end":38,"kind":"keyword","start":0,"text":"r19r18:"}]}
source_snippet:         r19r18: reg_pair = ["r19r18"],
context_before:         r17r16: reg_pair = ["r17r16"],
context_after:         r21r20: reg_pair = ["r21r20"],