code: def order_items_spec():
      return json.loads(
          r"""
  {
    "$schema": "https://vega.github.io/schema/vega/v5.json",
    "background": "white",
    "padding": 5,
    "height": 200,
    "style": "cell",
    "data": [
      {"name": "order_items", "url": "table://order_items"},
      {
        "name": "data_0",
        "source": "order_items",
        "transform": [
          {
            "type": "aggregate",
            "groupby": ["menu_item"],
            "ops": ["count"],
            "fields": ["menu_item"],
            "as": ["__count"]
          },
          {
              "type": "collect",
              "sort": {"field": ["menu_item"]}
          }
        ]
      }
    ],
    "signals": [
      {"name": "x_step", "value": 20},
      {
        "name": "width",
        "update": "bandspace(domain('x').length, 0.1, 0.05) * x_step"
      }
    ],
    "marks": [
      {
        "name": "layer_0_marks",
        "type": "rect",
        "clip": true,
        "style": ["bar"],
        "from": {"data": "data_0"},
        "encode": {
          "update": {
            "fill": {"value": "#4c78a8"},
            "x": {"scale": "x", "field": "menu_item"},
            "width": {"scale": "x", "band": 1},
            "y": {"scale": "y", "field": "__count"},
            "y2": {"scale": "y", "value": 0}
          }
        }
      }
    ],
    "scales": [
      {
        "name": "x",
        "type": "band",
        "domain": {"data": "data_0", "field": "menu_item", "sort": true},
        "range": {"step": {"signal": "x_step"}},
        "paddingInner": 0.1,
        "paddingOuter": 0.05
      },
      {
        "name": "y",
        "type": "linear",
        "domain": {"data": "data_0", "field": "__count"},
        "range": [{"signal": "height"}, 0],
        "nice": true,
        "zero": true
      }
    ]
  }
  """
      )
  
imports: import pandas
  import pytest
  from pandas import Timestamp, NaT
  import pyarrow
  import vegafusion
  import json
  import polars
  from datetime import date
  import decimal
  import base64
label_desc: Use image node_id 3 for calling a global function with example usage: order_items_spec() and returns: json