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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 request_cert(domain, master, ticket, port):
    '''
    Request CA cert from master icinga2 node.

    Returns::
        icinga2 pki request --host master.domain.tld --port 5665 --ticket TICKET_ID --key /etc/icinga2/pki/domain.tld.key --cert /etc/icinga2/pki/domain.tld.crt --trustedcert \
                /etc/icinga2/pki/trusted-master.crt --ca /etc/icinga2/pki/ca.crt

    CLI Example:

    .. code-block:: bash

        salt '*' icinga2.request_cert domain.tld master.domain.tld TICKET_ID

    '''
    result = __salt__['cmd.run_all'](["icinga2", "pki", "request", "--host", master, "--port", port, "--ticket", ticket, "--key", "{0}{1}.key".format(get_certs_path(), domain), "--cert",
                                      "{0}{1}.crt".format(get_certs_path(), domain), "--trustedcert", "{0}trusted-master.crt".format(get_certs_path()), "--ca", "{0}ca.crt".format(get_certs_path())], python_shell=False)
    return result