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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 _predicate(self, i):
 """Given a valid datetime or slace, return the predicate portion of the SQL query, a boolean indicating whether multiple items are expected from the result, and a dictionary of parameters for the query """

        if isinstance(i, slice):
            if i.step is not None:
                raise TypeError("Slice step not permitted")
            if ( (i.start is not None and not isinstance(i.start, datetime))
                or (i.stop is not None and not isinstance(i.stop, datetime))
            ):
                raise TypeError(
                    "Slice indices must be {} or None".format(datetime)
                )
            if i.start is not None and i.stop is not None:
                if i.start > i.stop:
                    raise ValueError(
                        "Start index is greater than the End index"
                    )
                else:
                    # Substitution of the key coloumn, but the
                    # parameters themselves will be substituted by sqlite3
                    predicate = "WHERE {} BETWEEN :start AND :stop".format(
                        self._keycol
                    )
            elif i.start is not None:
                # i.stop will also be None
                predicate = "WHERE {} >= :start".format(self._keycol)
            elif i.stop is not None:
                # i.start will also be None
                predicate = "WHERE {} <= :stop".format(self._keycol)
            else:
                # both are None, so equivelent to wanting everything
                predicate = ""
            multi = True
            pred = {"start": i.start, "stop": i.stop}
        elif isinstance(i, datetime):
            # Substitution of the key coloumn, but the
            # parameters themselves will be substituted by sqlite3
            predicate = "WHERE {} = :key".format(self._keycol)
            multi = False
            pred = {"key": i}
        else:
            # not a slice or a datetime object
            raise TypeError("List indices must be {}".format(datetime))
        # predicate is the end of the query string.
        # multi is a boolean indicating whether the result should be iterable
        # or not. pred is a dict of the parameters for substitution
        return (predicate, multi, pred)