Throw an error if wrong key type is used

Author: awalker4

src/unstructured_client/users.py

@@ -10,7 +10,6 @@
 # region imports
 from cryptography import x509
 from cryptography.hazmat.primitives import serialization, hashes
-from cryptography.hazmat.primitives.serialization import load_pem_public_key
 from cryptography.hazmat.primitives.asymmetric import padding, rsa
 from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
 from cryptography.hazmat.backends import default_backend
@@ -481,6 +480,9 @@ def _encrypt_rsa_aes(
             backend=default_backend()
         )
 
+        if not isinstance(public_key, rsa.RSAPublicKey):
+            raise TypeError("Public key must be an RSA public key for envelope encryption.")
+
         # Generate a random AES key
         aes_key = os.urandom(32)  # 256-bit AES key
 
@@ -523,6 +525,9 @@ def _encrypt_rsa(
             backend=default_backend()
         )
 
+        if not isinstance(public_key, rsa.RSAPublicKey):
+            raise TypeError("Public key must be an RSA public key for encryption.")
+
         ciphertext = public_key.encrypt(
             plaintext.encode(),
             padding.OAEP(