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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fill_in_datakeys(example_parameters, dexdata):
 """Update the 'examples dictionary' _examples.example_parameters. If a datakey (key in 'datafile dictionary') is not present in the 'examples dictionary' it is used to initialize an entry with that key. If not specified otherwise, any 'exkey' (key in 'examples dictionary') is used as 'datakey'. """

    # default initialization of 'datakey' key with entries from data dictionary
    for exkey in example_parameters:
        if 'datakey' not in example_parameters[exkey]:
            if exkey in dexdata:
                example_parameters[exkey]['datakey'] = exkey
            else:
                example_parameters[exkey]['datakey'] = 'unspecified in dexdata'
    return example_parameters