{
  "source_variable_1": {
    "type": "variable",
    "default": {
      "name": "Default",
      "values": "val1"
    },
    "properties": [
      {
        "type": "type",
        "name": "string"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "path": "source_variable_1",
    "names": [
      "source_variable_1"
    ],
    "description": "The first source variable."
  },
  "source_variable_2": {
    "type": "variable",
    "default": {
      "name": "Default",
      "values": "val2"
    },
    "properties": [
      {
        "type": "type",
        "name": "string"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "path": "source_variable_2",
    "names": [
      "source_variable_2"
    ],
    "description": "The second source variable."
  },
  "my_variable": {
    "type": "variable",
    "default": {
      "name": "Default",
      "values": "val1"
    },
    "properties": [
      {
        "type": "type",
        "name": "choice"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "choices": {
      "name": "Choices",
      "values": [
        "the value of the variable \"source_variable_1\"",
        "the value of the variable \"source_variable_2\""
      ]
    },
    "path": "my_variable",
    "names": [
      "my_variable"
    ],
    "description": "A variable."
  }
}