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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 split_and_operate(self, mask, f, inplace):
 """ split the block per-column, and apply the callable f per-column, return a new block for each. Handle masking which will not change a block unless needed. Parameters mask : 2-d boolean mask f : callable accepting (1d-mask, 1d values, indexer) inplace : boolean Returns ------- list of blocks """


        if mask is None:
            mask = np.ones(self.shape, dtype=bool)
        new_values = self.values

        def make_a_block(nv, ref_loc):
            if isinstance(nv, Block):
                block = nv
            elif isinstance(nv, list):
                block = nv[0]
            else:
                # Put back the dimension that was taken from it and make
                # a block out of the result.
                try:
                    nv = _block_shape(nv, ndim=self.ndim)
                except (AttributeError, NotImplementedError):
                    pass
                block = self.make_block(values=nv,
                                        placement=ref_loc)
            return block

        # ndim == 1
        if self.ndim == 1:
            if mask.any():
                nv = f(mask, new_values, None)
            else:
                nv = new_values if inplace else new_values.copy()
            block = make_a_block(nv, self.mgr_locs)
            return [block]

        # ndim > 1
        new_blocks = []
        for i, ref_loc in enumerate(self.mgr_locs):
            m = mask[i]
            v = new_values[i]

            # need a new block
            if m.any():
                nv = f(m, v, i)
            else:
                nv = v if inplace else v.copy()

            block = make_a_block(nv, [ref_loc])
            new_blocks.append(block)

        return new_blocks