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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 _fields_list_to_dict(fields):
 """Takes a list of field names and returns a matching dictionary. ["a", "b"] becomes {"a": 1, "b": 1} and ["a.b.c", "d", "a.c"] becomes {"a.b.c": 1, "d": 1, "a.c": 1} """

    for key in fields:
        assert isinstance(key, (str,unicode))
    return dict([[key, 1] for key in fields])