xdr/price.go
func (p *Price) String() string {
	return big.NewRat(int64(p.N), int64(p.D)).FloatString(7)
}
func (p *Price) String() string {
	return big.NewRat(int64(p.N), int64(p.D)).FloatString(7)
}
// String returns a string represenation of `p`