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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 split_identifiers(identifiers=[], proportions={}):
 """ Split the given identifiers by the given proportions. Args: identifiers (list):
 List of identifiers (str). proportions (dict):
 A dictionary containing the proportions with the identifier from the input as key. Returns: dict: Dictionary containing a list of identifiers per part with the same key as the proportions dict. Example:: {'melvin' : ['a', 'c'], 'timmy' : ['b', 'd']} """


    abs_proportions = absolute_proportions(proportions, len(identifiers))

    parts = {}
    start_index = 0

    for idx, proportion in abs_proportions.items():
        parts[idx] = identifiers[start_index:start_index + proportion]
        start_index += proportion

    return parts