class_docstr: _Locations store code locations(file, linenos).
class_docstr_tok: ["_Locations","store","code","locations","(","file",",","linenos",")","."]
code: def add(self, file, lineno):
      if file in self and lineno not in self[file]:
          self[file].append(lineno)
      else:
          self[file] = [lineno]
  
imports: from __future__ import print_function, division, absolute_import
  import collections
label_desc: Use image node_id 2 for calling the _Locations obj's underlying member method code with example usage: obj.add(file, lineno) without return types