code: function fromPrototype(assignment) {
    const left = assignment.node.left;
    if (!left) {
      return null;
    }
  
    if (
      t.isMemberExpression(left) &&
      left.object &&
      t.isMemberExpression(left.object) &&
      left.object.property.identifier === "prototype"
    ) {
      return left.object.object.name;
    }
  
    return null;
  }
docs: the function class is inferred from a prototype assignment e.g. TodoClass.prototype.render = function() {}