ECC NIST P-521 key taken from
https://sites.google.com/site/brainhub/pgpecckeys

The sample key has ECDSA top key 0x6B4184E145AF2FFE and a single ECDH
encryption subkey 0x07EAAA48A81C4838. ECDH subkey uses SHA-512 and
AES-256 with KDF. The password for the key is "ecc".

-----BEGIN PGP PRIVATE KEY BLOCK-----
Version: PGP Command Line v10.0.0 (Linux)
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=Qnd8
-----END PGP PRIVATE KEY BLOCK-----