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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 install_PMK(self):
 """Compute and install the PMK"""

        self.pmk = PBKDF2HMAC(
            algorithm=hashes.SHA1(),
            length=32,
            salt=self.ssid.encode(),
            iterations=4096,
            backend=default_backend(),
        ).derive(self.passphrase.encode())