code: def _looks_like_script(self, path):
          
          fp = open(path, 'rb')
          try:
              sample = fp.read(512).decode('latin-1')
              return not set(sample).difference(string.printable)
          finally:
              fp.close()
docs: Return :data:`True` if the (possibly extensionless) file at `path`
          resembles a Python script. For now we simply verify the file contains
          ASCII text.