For asymmetric keys, this property represents the type of the key. Supported key types are:

• 'rsa' (OID 1.2.840.113549.1.1.1)
• 'rsa-pss' (OID 1.2.840.113549.1.1.10)
• 'dsa' (OID 1.2.840.10040.4.1)
• 'ec' (OID 1.2.840.10045.2.1)
• 'x25519' (OID 1.3.101.110)
• 'x448' (OID 1.3.101.111)
• 'ed25519' (OID 1.3.101.112)
• 'ed448' (OID 1.3.101.113)
• 'dh' (OID 1.2.840.113549.1.3.1)

This property is undefined for unrecognized KeyObject types and symmetric keys.