func Timestamp() (cty.Value, error) {
	return TimestampFunc.Call([]cty.Value{})
}
Timestamp returns a string representation of the current date and time.

In the Terraform language, timestamps are conventionally represented as
strings using RFC 3339 "Date and Time format" syntax, and so timestamp
returns a string in this format.
package funcs
import (
	"time"
	"github.com/zclconf/go-cty/cty"
	"github.com/zclconf/go-cty/cty/function"
)
var TimestampFunc = function.New(&function.Spec{
	Params: []function.Parameter{},
	Type:   function.StaticReturnType(cty.String),
	Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) {
		return cty.StringVal(time.Now().UTC().Format(time.RFC3339)), nil
	},
})
var TimeAddFunc = function.New(&function.Spec{
	Params: []function.Parameter{
		{
			Name: "timestamp",
			Type: cty.String,
		},
		{
			Name: "duration",
			Type: cty.String,
		},
	},
	Type: function.StaticReturnType(cty.String),
	Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) {
		ts, err := time.Parse(time.RFC3339, args[0].AsString())
		if err != nil {
			return cty.UnknownVal(cty.String), err
		}
		duration, err := time.ParseDuration(args[1].AsString())
		if err != nil {
			return cty.UnknownVal(cty.String), err
		}
		return cty.StringVal(ts.Add(duration).Format(time.RFC3339)), nil
	},
})