What is the best way to implement nested dictionaries?

Question

I have a data structure which essentially amounts to a nested dictionary. Let\'s say it looks like this:

{\'new jersey\': {\'mercer county\': {\'plumbers\':          


        

Answer 1

For the following (copied from above) is there a way to implement the append function. I am trying to use a nested dictionary to store values as array.

class Vividict(dict):
    def __missing__(self, key):
        value = self[key] = type(self)() # retain local pointer to value
    return value  

My current implementation is as follows:

totalGeneHash=Vividict()
        
for keys in GenHash:
    for second in GenHash[keys]:
        if keys in sampleHash:
            total_val = GenHash[keys][second]
                totalGeneHash[gene][keys].append(total_val)
This is the error I get: AttributeError: 'Vividict' object has no attribute 'append'