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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 _rsadp(self, c):
 """ Internal method providing raw RSA decryption, i.e. simple modular exponentiation of the given ciphertext representative 'c', a long between 0 and n-1. This is the decryption primitive RSADP described in PKCS#1 v2.1, i.e. RFC 3447 Sect. 5.1.2. Input: c: ciphertest representative, a long between 0 and n-1, where n is the key modulus. Output: ciphertext representative, a long between 0 and n-1 Not intended to be used directly. Please, see encrypt() method. """


        n = self.modulus
        if type(c) is int:
            c = long(c)        
        if type(c) is not long or c > n-1:
            warning("Key._rsaep() expects a long between 0 and n-1")
            return None

        return self.key.decrypt(c)