Are you trying to for this key, or is this part of a specific online puzzle or game?
If you are looking for the "piece" that corresponds to this key (such as the public address it controls), you would need to import it into a secure Bitcoin wallet or use a local offline tool to derive the public address. cDWFjmPB2JVi1wN4gciWAXjMeGrCjkaqlcquWEiAGIZ9Zzp...
Users attempting to recover an old wallet from a printed "paper wallet" or backup. Are you trying to for this key, or
The string provided appears to be a in Wallet Import Format (WIF). cDWFjmPB2JVi1wN4gciWAXjMeGrCjkaqlcquWEiAGIZ9Zzp...
Developers using dummy keys for testing software on the Bitcoin network.