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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 createClientCertificate(self, name, noPass = True, keyLength = 2048, days = 375):
 """Create a client certificate """

        if not name:
            raise ValueError('Require name')
        configPath, keyPath, csrPath, certPath = \
                os.path.join(self.basePath, self.FILE_CONFIG), \
                os.path.join(self.basePath, self.DIR_PRIVATE, '%s.key.pem' % name), \
                os.path.join(self.basePath, self.DIR_CSR, '%s.csr.pem' % name), \
                os.path.join(self.basePath, self.DIR_CERTS, '%s.cert.pem' % name)
        if os.path.isfile(keyPath):
            raise ValueError('Key file exists at [%s]' % keyPath)
        if os.path.isfile(csrPath):
            raise ValueError('CSR file exists at [%s]' % csrPath)
        if os.path.isfile(certPath):
            raise ValueError('Certificate file exists at [%s]' % certPath)
        # Generate the key
        if subprocess.call([ 'openssl', 'genrsa', '-aes256', '-out', keyPath, str(keyLength) ] if not noPass else [ 'openssl', 'genrsa', '-out', keyPath, str(keyLength) ]) != 0:
            raise ValueError('Failed to create key')
        # Generate the csr
        if subprocess.call([ 'openssl', 'req', '-config', configPath, '-key', keyPath, '-new', '-sha256', '-out', csrPath ]) != 0:
            raise ValueError('Failed to create CSR')
        # Generate the certificate
        if subprocess.call([ 'openssl', 'ca', '-config', configPath, '-extensions', 'usr_cert', '-days', str(days), '-notext', '-md', 'sha256', '-in', csrPath, '-out', certPath ]) != 0:
            raise ValueError('Failed to create certificate')