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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_private_key(pem_path, passphrase_bytes=None):
 """Load private key from PEM encoded file"""

    with open(pem_path, "rb") as f:
        return cryptography.hazmat.primitives.serialization.load_pem_private_key(
            data=f.read(),
            password=passphrase_bytes,
            backend=cryptography.hazmat.backends.default_backend(),
        )