code: def looks_lib(fname):
      """Returns True if the given filename looks like a dynamic library.
      Based on extension, but cross-platform and more flexible.
      """
      fname = fname.lower()
      if sys.platform.startswith("win"):
          return fname.endswith(".dll")
      elif sys.platform.startswith("darwin"):
          return fname.endswith(".dylib")
      else:
          return fname.endswith(".so") or ".so." in fname
  
imports: import os
  import sys
  import ctypes
label_desc: Use image node_id 1 for calling a global function with example usage: looks_lib(fname) and returns: fname, fname, unknown