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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 astra_algorithm(direction, ndim, vol_id, sino_id, proj_id, impl):
 """Create an ASTRA algorithm object to run the projector. Parameters direction : {'forward', 'backward'} For ``'forward'``, apply the forward projection, for ``'backward'`` the backprojection. ndim : {2, 3} Number of dimensions of the projector. vol_id : int Handle for the ASTRA volume data object. sino_id : int Handle for the ASTRA projection data object. proj_id : int Handle for the ASTRA projector object. impl : {'cpu', 'cuda'} Implementation of the projector. Returns ------- id : int Handle for the created ASTRA internal algorithm object. """

    if direction not in ('forward', 'backward'):
        raise ValueError("`direction` '{}' not understood".format(direction))
    if ndim not in (2, 3):
        raise ValueError('{}-dimensional projectors not supported'
                         ''.format(ndim))
    if impl not in ('cpu', 'cuda'):
        raise ValueError("`impl` type '{}' not understood"
                         ''.format(impl))
    if ndim == 3 and impl == 'cpu':
        raise NotImplementedError(
            '3d algorithms for CPU not supported by ASTRA')
    if proj_id is None and impl == 'cpu':
        raise ValueError("'cpu' implementation requires projector ID")

    algo_map = {'forward': {2: {'cpu': 'FP', 'cuda': 'FP_CUDA'},
                            3: {'cpu': None, 'cuda': 'FP3D_CUDA'}},
                'backward': {2: {'cpu': 'BP', 'cuda': 'BP_CUDA'},
                             3: {'cpu': None, 'cuda': 'BP3D_CUDA'}}}

    algo_cfg = {'type': algo_map[direction][ndim][impl],
                'ProjectorId': proj_id,
                'ProjectionDataId': sino_id}
    if direction is 'forward':
        algo_cfg['VolumeDataId'] = vol_id
    else:
        algo_cfg['ReconstructionDataId'] = vol_id

    # Create ASTRA algorithm object
    return astra.algorithm.create(algo_cfg)