pip install gdx2py

>>> from gdx2py import GdxFile, GAMSSet, GAMSScalar, GAMSParameter
>>> with GdxFile('/path/to/gdx/file.gdx', mode='w') as gdx:
>>>     gdx['set1'] = ['a', 'b', 'c']  # Write a simple set
>>>     set1 = gdx['set1']  # Read a symbol
>>>     # Write a 2-dimensional set
>>>     gdx['set2'] = [('a', 'foo'), ('b', 'bar'), ('c', 'baz')]
>>>     # Write a scalar with explanatory text
>>>     gdx['scalar'] = GAMSScalar(3.14, expl_text="Value of pi")  
>>>     # Write a parameter with domain                                     
>>>     gdx['par1'] = GAMSParameter({'a': 1, 'b': 2,  
                                     'c': 3, 'd': 4 }, 
                                    domain=['set1'])