def dictionary_union(dict1, dict2):
    """Take two dictionaries, return dictionary union.

    Parameters:
    -----------
    dict1: Python dictionary
    dict2: Python dictionary

    Returns:
    --------
    A union of the dictionaries. It assumes that values
    with the same keys are identical.
    """
    keys1 = list(dict1.keys())
    keys2 = list(dict2.keys())
    result = {}
    for key1 in keys1:
        result[key1] = dict1[key1]
    for key2 in keys2:
        result[key2] = dict2[key2]
    return result