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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 get_value(self, name, parameters=None):
 """Return the value of a cached variable if applicable The value of the variable 'name' is returned, if no parameters are passed or if all parameters are identical to the ones stored for the variable. :param str name: Name of teh variable :param dict parameters: Current parameters or None if parameters do not matter :return: The cached value of the variable or None if the parameters differ """

        if not isinstance(parameters, dict):
            raise TypeError("parameters must a dict")
        if name not in self._cache:
            return None
        hash = self._parameter_hash(parameters)
        hashdigest = hash.hexdigest()
        return self._cache[name].get(hashdigest, None)