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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 scatter(h1: Histogram1D, **kwargs) -> dict: """Scatter plot of 1D histogram values. Points are horizontally placed in bin centers. Parameters shape : str """

    shape = kwargs.pop("shape", DEFAULT_SCATTER_SHAPE)
    # size = kwargs.pop("size", DEFAULT_SCATTER_SIZE)

    mark_template = [{
        "type": "symbol",
        "from": {"data": "series"},
        "encode": {
            "enter": {
                "x": {"scale": "xscale", "field": "x"},
                "y": {"scale": "yscale", "field": "y"},
                "shape": {"value": shape},
                # "size": {"value": size},
                "fill": {"scale": "series", "field": "c"},
            },
        }
    }]
    vega = _scatter_or_line(h1, mark_template=mark_template, kwargs=kwargs)
    return vega