Maximum recursion depth exceeded

[Shaunakde]

I am using flap to flatten a fairly standard journal file. When I run the command flap source.tex out.tex I get the following error:

 File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 153, in _evaluate_until
    tokens += self._evaluate_one()
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 138, in _evaluate_one
    return self.evaluate_command(str(self._next_token))
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 164, in evaluate_command
    return macro.invoke(self)
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/macros.py", line 124, in invoke
    return self._execute(parser, invocation)
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/macros.py", line 150, in _execute
    return parser._spawn(self._body, invocation.arguments)._evaluate_group()
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 146, in _evaluate_group
    tokens = self._evaluate_until(lambda token: token.ends_a_group)
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 153, in _evaluate_until
    tokens += self._evaluate_one()
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 138, in _evaluate_one
    return self.evaluate_command(str(self._next_token))
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 161, in evaluate_command
    if command not in self._definitions:
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 43, in __contains__
    return key in self._definitions or (self._parent and key in self._parent)
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 43, in __contains__
    return key in self._definitions or (self._parent and key in self._parent)
  File "/home/shaunak/anaconda/envs/Python3x/lib/python3.6/site-packages/flap/latex/parser.py", line 43, in __contains__
    return key in self._definitions or (self._parent and key in self._parent)
  [Previous line repeated 77 more times]
RecursionError: maximum recursion depth exceeded

My python version is:

Python 3.6.2 |Continuum Analytics, Inc.| (default, Jul 20 2017, 13:51:32) 
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)] on linux

I have attached the directory structure of the project to this issue. The main file is called 0_Trento_2016.tex. There are image files in the Figures folder.

TREE.txt