Merge dicts without override

[DeaD_EyE]

Generalized version to use as many dicts as you want.
All values of the dicts must be dicts, otherwise this code won't work.

import pprint


d1 = {
    "10084": {
        "aliases": {
            "first_last": "Loren Meyer",
            "last_first": "Meyer, Loren"
        }
    },
    "10111": {
        "aliases": {
            "first_last": "Cory Higgins",
            "last_first": "Higgins, Cory"
        }
    },
    "10163": {
        "aliases": {
            "first_last": "Antoine Wright",
            "last_first": "Wright, Antoine"
        }
    }
}
 
#vitals dict
d2 = {
    "10084": {
        "vitals": {
            "ht": 82,
            "wt": 257,
            "birth_date": "12/30/1972"
        }
    },
    "10111": {
        "vitals": {
            "ht": 77,
            "wt": 180,
            "birth_date": "6/14/1989"
        }
    },
    "10163": {
        "vitals": {
            "ht": 79,
            "wt": 210,
            "birth_date": "2/6/1984"
        }
    }
}
 
#combine dict
d3 = {
    "10084": {
        "combine": {
            "span": 81.0,
            "reach": 100.0,
            "body_fat": 4.1,
        }
    },
    "10111": {
        "combine": {
            "span": 81.0,
            "reach": 100.0,
            "body_fat": 9.1,
        }
    },
    "10163": {
        "combine": {
            "span": 75.0,
            "reach": 85.0,
            "body_fat": 6.1,
        }
    }
}


def combine_subdicts(*dicts):
    if len(dicts) < 2:
        raise ValueError('Minimum two dicts are required to combine')
    result = {}
    for uid, data in dicts[0].items():
        try:
            for subdict in dicts[1:]:
                data.update(subdict[uid])
        except KeyError:
            print(f'Inconsistent. Missing id {uid} in {subdict}')
            continue
        result[uid] = data
    return result


combined_dict = combine_subdicts(d1, d2, d3)
pprint.pprint(combined_dict, indent=2)

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Output:
{ '10084': { 'aliases': { 'first_last': 'Loren Meyer',
                          'last_first': 'Meyer, Loren'},
             'combine': {'body_fat': 4.1, 'reach': 100.0, 'span': 81.0},
             'vitals': {'birth_date': '12/30/1972', 'ht': 82, 'wt': 257}},
  '10111': { 'aliases': { 'first_last': 'Cory Higgins',
                          'last_first': 'Higgins, Cory'},
             'combine': {'body_fat': 9.1, 'reach': 100.0, 'span': 81.0},
             'vitals': {'birth_date': '6/14/1989', 'ht': 77, 'wt': 180}},
  '10163': { 'aliases': { 'first_last': 'Antoine Wright',
                          'last_first': 'Wright, Antoine'},
             'combine': {'body_fat': 6.1, 'reach': 85.0, 'span': 75.0},
             'vitals': {'birth_date': '2/6/1984', 'ht': 79, 'wt': 210}}}