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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_evidence(self, evidence_dict, time_slice, shift):
 """ Getting the evidence belonging to a particular timeslice. Parameters: evidence: dict a dict key, value pair as {var: state_of_var_observed} None if no evidence time: int the evidence corresponding to the time slice shift: int shifting the evidence corresponding to the given time slice. """

        if evidence_dict:
            return {(node[0], shift): evidence_dict[node] for node in evidence_dict if node[1] == time_slice}