## getCodeBySystem() function 
Tries to find a code string for a given system within a given codeable concept.

**Signature:**
```typescript
export declare function getCodeBySystem(concept: CodeableConcept, system: string): string | undefined;
```

## Parameters 
| Parameter | Type | Description |
| --- | --- | --- |
| concept | CodeableConcept | The codeable concept. |
| system | string | The system string. |

**Returns:**
string \| undefined

The code if found; otherwise undefined.