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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 _loads(self, data_string, layer=None, source=None):
 """Load data from a yaml formatted string. Parameters data_string : str yaml formatted string. The root element of the document should be an associative array layer : str layer to load data into. If none is supplied the outermost one is used source : str Source to attribute the values to """

        data_dict = yaml.full_load(data_string)
        self._read_dict(data_dict, layer, source)