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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 load(self, executable):
 """ Initialize a QAM into a fresh state. :param executable: Load a compiled executable onto the QAM. """

        if self.status == 'loaded':
            warnings.warn("Overwriting previously loaded executable.")
        assert self.status in ['connected', 'done', 'loaded']

        self._variables_shim = {}
        self._executable = executable
        self._bitstrings = None
        self.status = 'loaded'
        return self