Can't provide WALLET_PRIVATE_KEY env

I am not sure exactly what I am doing wrong but no matter what I try I can not get it to recognize my private key. The command in the readme does not work I get:
WALLET_PRIVATE_KEY=0x (private key) : The term
'WALLET_PRIVATE_KEY=0x(private key) ' is not recognized as the name of a cmdlet, function,
script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ WALLET_PRIVATE_KEY='0x(private key) ...
+ ~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (WALLETPRIVATE...(private key) :String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException.

Check the command in the README against the PowerShell error shown in the issue. Document a PowerShell-compatible way to provide WALLET_PRIVATE_KEY, and verify that the README instructions no longer produce the reported command-not-found error.

Written by the indexing model from the issue text.