<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def _multi_lines(self, strands, permutation):
        '''Prepares lines to write to file for pfunc command input.

        :param strand: Strand input (cr.DNA or cr.RNA).
        :type strand: cr.DNA or cr.DNA
        :param permutation: Permutation (e.g. [1, 2, 3, 4]) of the type used
                            by pfunc_multi.
        :type permutation: list
        '''
        lines = []
        # Write the total number of distinct strands
        lines.append(str(len(strands)))
        # Write the distinct strands
        lines += [str(strand) for strand in strands]
        # Write the permutation
        lines.append(' '.join(str(p) for p in permutation))

        return lines