Write config.py dynamically

Question

I have to write a config file based on the parameters given by a user.

The goal is to obtain something like that in the target file :

PrimerGCRange = namedtuple("GCRange", "min max opt")
PRIMER_SIZE_RANGES = {
        "DEFAULT": PrimerSizeRange(25, 35, 30),
        "HIGH_GC": PrimerSizeRange(25, 35, 30),
    }

How can I have that without the lines becoming :

PRIMER_SIZE_RANGES = {"DEFAULT": [25, 35, 30], "HIGH_GC": [25, 35, 30]}

The idea is to have a dictionary where {"PRIMER_SIZE_RANGE" : "DEFAULT": PrimerSizeRange(25, 35, 30), ..}, with 25, 35, 30 the inputs of the user, is put in form by a function. Then I write this in a new file but I don't want the PrimerSizeRange to be evaluating as the destination file is a config.py.

Otherwise the namedtuple can't be used properly in others files.

Here I transform the dictionary to text

    for v in values:
        text += v + ' = ' + json.dumps(values[v]) + '\n'

    with open(file_name, 'w') as f:
        f.write(textwrap.dedent(text))

where values would be something like :

values = {
    "PRIMER_SIZE_RANGES": {
        "DEFAULT": PrimerSizeRange(25, 35, 30),
        "HIGH_GC": PrimerSizeRange(25, 35, 30),
    },
    "PREFIX" : "scheme",
    "OUTPUT_PATH" : "./output",
    "MAX_ALN_GAP_PERCENT" : 0.03,
    "MAX_REFERENCES" : 200
}

And the expected config.py :

PrimerSizeRange = namedtuple("PrimerSizeRange", "min max opt")
PRIMER_SIZE_RANGES = {
    "DEFAULT": PrimerSizeRange(25, 35, 30),
    "HIGH_GC": PrimerSizeRange(25, 35, 30),
}

PREFIX = "scheme"
OUTPUT_PATH = "./output"
MAX_ALN_GAP_PERCENT = 0.03
MAX_REFERENCES = 200