code: function isNormalFunctionExpression (node) {
    return (node.type === 'FunctionExpression' || node.type === 'ArrowFunctionExpression') && !node.generator && !node.async
  }
docs: ----------------------------------------------------------------------------- Helpers ----------------------------------------------------------------------------- 
  Determines whether a node is a 'normal' (i.e. non-async, non-generator) function expression.
  @param {ASTNode} node The node in question
  @returns {boolean} `true` if the node is a normal function expression