class_docstr: Convenience class to encapsulate tractogram file format.
class_docstr_tok: ["Convenience","class","to","encapsulate","tractogram","file","format","."]
code: def tractogram(self):
      return self._tractogram
  
imports: from abc import ABC, abstractmethod
  from .header import Field
label_desc: Use image node_id 2 for calling the TractogramFile obj's underlying member method code with example usage: obj.tractogram() and returns: self