Promote row to header leads to endless execution errors with NaN column headers

[aarondr77]

1. Import Sheet 1 MitoTesting.xlsx

2. Promote the first row to header

3. Make any edit and get this execution error. The only edits that you can make are deleting the columns nan (1), nan (2), etc. But deleting any other column (including nan), adding a column, etc results in the following execution error

  File "step_performer.py", line 156, in execute_through_transpile
    exec(final_code, exec_globals, exec_locals)
  File "<string>", line 1, in <module>
NameError: name 'nan' is not defined