import re
zz = 'options={}, params={vector_name=get_x, default_like_count=2, setting_id=1200, system=0 back options={}, params={vector_name=get_x, default_like_count=2, setting_id=1200, system=0 back'
m = re.search(r'vector_name=(\w+)', zz)
if m:
	print(m.group(1))