Load both files and parse them

params.py

import json
import yaml

f = open('myparamfile.json')
dataParam = json.load(f)
f.close()

with open('mytemplatefile.yaml', 'r') as y:
    dataTemplate = yaml.load(y, Loader=yaml.BaseLoader)

paramListInParamFile = []
for k in dataParam:
    paramListInParamFile.append(k['ParameterKey'])

paramListInTemplateFile = []
for kk in dataTemplate['Parameters']:
    paramListInTemplateFile.append(kk)

paramListInParamFile.sort()
paramListInTemplateFile.sort()