(Chilkat2-Python) Convert RSA Private Key to Public Key

Demonstrates how to get a public RSA key from a private RSA key.

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import sys
import chilkat2

key = chilkat2.PrivateKey()

# Step 1: Load the private key from a source.
# (Chilkat can load private keys from all types of formats, and from in-memory bytes or encoded strings.
# see the online reference documentation for more options.)
success = key.LoadPemFile("qa_data/pem/VP_Private.pem")
if (success != True):
    print(key.LastErrorText)
    sys.exit()

# Step 2: Get the public key object from the private key object.
# pubKey is a CkPublicKey
pubKey = key.GetPublicKey()
if (key.LastMethodSuccess != True):
    print(key.LastErrorText)
    sys.exit()

# Step 3: Save the public key in a desired format. 
# (Chilkat can load or save public and private keys in many different formats.  See
# the online reference documentation for more options.)

# Saves to a PKCS8 PEM file.
bPreferPkcs1 = False
success = pubKey.SavePemFile(bPreferPkcs1,"qa_data/pem/VP_Public.pem")
if (pubKey.LastMethodSuccess != True):
    print(pubKey.LastErrorText)
    sys.exit()

print("Extracted and saved public key from private key.")