func (m *CodeDescriptionMapping) deriveCodeAndDescription(code string, description string) (string, string) {
	if code == "" {
		code = m.descriptionToCode[description]
	}
	if description == "" {
		description = m.codeToDescription[code]
	}
	return code, description
}
deriveCodeAndDescription derives the code from the description of the description from the code,
depending on the parameters specified.
If the code is not specified (ie: empty string), it derives it from the description, and if the description
is not specified (ie: empty string), it derives it from the code.
Returns both: code and the description.
package codedelement
import (
	"math/rand"
	"time"
	"github.com/google/simhospital/pkg/clock"
	"github.com/google/simhospital/pkg/config"
	"github.com/google/simhospital/pkg/ir"
	"github.com/google/simhospital/pkg/pathway"
	"github.com/google/simhospital/pkg/sample"
)
type CodeDescriptionMapping struct {
	codeToDescription map[string]string
	descriptionToCode map[string]string
}
func (m *CodeDescriptionMapping) Add(code string, description string) {
	m.codeToDescription[code] = description
	m.descriptionToCode[description] = code
}