code: def is_valid_line_name(name):
      return (
          isinstance(name, str)
          and re.match(r"^[a-zA-Z_][-a-zA-Z_0-9.]*", name) != None
      )
  
imports: from __future__ import print_function
  from __future__ import division
  import re
  import sys
label_desc: Use image node_id 7 for calling a global function with example usage: is_valid_line_name(name) and returns: unknown