func FromString(timestamp string) (int64, error) {
	var err error
	stringTimestamp := strings.Split(timestamp, ".")
	if len(stringTimestamp) < 2 {
		return 0, errors.New("invalid timestamp provided")
	}
	seconds, err := strconv.ParseInt(stringTimestamp[0], 10, 64)
	if err != nil {
		return 0, errors.New("invalid timestamp seconds provided")
	}
	nano, err := strconv.ParseInt(stringTimestamp[1], 10, 64)
	if err != nil {
		return 0, errors.New("invalid timestamp nanos provided")
	}
	return seconds*nanosInSecond + nano, nil
}
FromString parses a string in the format `{seconds}.{nanos}` into int64 timestamp
package timestamp
import (
	"errors"
	"fmt"
	"strconv"
	"strings"
	"time"
)
const (
	nanosInSecond = 1000000000
)