How to use the mappy.Aligner function in mappy

print("  -r INT      band width")
		print("  -c          output the cs tag")
		sys.exit(1)

	preset = min_cnt = min_sc = k = w = bw = None
	out_cs = False
	for opt, arg in opts:
		if opt == '-x': preset = arg
		elif opt == '-n': min_cnt = int(arg)
		elif opt == '-m': min_chain_score = int(arg)
		elif opt == '-r': bw = int(arg)
		elif opt == '-k': k = int(arg)
		elif opt == '-w': w = int(arg)
		elif opt == '-c': out_cs = True

	a = mp.Aligner(args[0], preset=preset, min_cnt=min_cnt, min_chain_score=min_sc, k=k, w=w, bw=bw)
	if not a: raise Exception("ERROR: failed to load/build index file '{}'".format(args[0]))
	for name, seq, qual in mp.fastx_read(args[1]): # read one sequence
		for h in a.map(seq, cs=out_cs): # traverse hits
			print('{}\t{}\t{}'.format(name, len(seq), h))

trans_start: Start position of the transcription(required in RNA mode).
        alignment: If requrie alignment.
    """
    with h5py.File(input_f,'r') as input_fh:
        raw_entry = list(input_fh['/Raw/Reads'].values())[0]
        raw_signal = raw_entry['Signal'].value
        raw_seq = input_fh[BASECALL_ENTRY+'/BaseCalled_template/Fastq'].value
        if mode !=0:
            assert trans_start is not None
            raw_signal,raw_seq,decap_event = _decap(input_fh,trans_start,raw_signal,raw_seq)
        else:
            decap_event = input_fh[BASECALL_ENTRY+'/BaseCalled_template/Events'].value
        align = None
        ref_seq = None
        if alignment:
            ref = mappy.Aligner(ref_f,preset = "map-ont",best_n = 5)
            aligns = ref.map(raw_seq.split(b'\n')[1])
            maxmapq = -np.inf
            for aln in aligns:
                if aln.mapq > maxmapq:
                    maxmapq = aln.mapq
                    align = aln
            if align is None:
                print("FAIL MAPPING "+input_f)
            else:
                if align.strand == -1:
                    ref_seq = mappy.revcomp(ref.seq(align.ctg,start = align.r_st,end = align.r_en))
                else:
                    ref_seq = ref.seq(align.ctg,start = align.r_st,end = align.r_en)
        if (mode == 1) or (mode == -1):
            raw_signal = raw_signal[::-1]
    if ref_seq is None and alignment:

import os
import io
import re
import sys
import queue
import traceback
import threading

# pip allows tombo install without correct version of mappy, so check here
try:
    import mappy
    if sys.version_info[0] > 2:
        mappy.Aligner(os.path.devnull).seq('')
    else:
        mappy.Aligner(os.path.devnull).seq(b'')
except AttributeError:
    th.error_message_and_exit('Tombo requires mappy version >= 2.10.')

# Future warning from cython in h5py
import warnings
warnings.simplefilter(action='ignore', category=FutureWarning)
import h5py

import numpy as np
np.seterr(all='raise')
import multiprocessing as mp

from tqdm import tqdm
from tqdm._utils import _term_move_up

from time import sleep

print("  -m INT      mininum chaining score")
		print("  -k INT      k-mer length")
		print("  -w INT      minimizer window length")
		print("  -r INT      band width")
		sys.exit(1)

	preset, min_cnt, min_sc, k, w, bw = None, None, None, None, None, None
	for opt, arg in opts:
		if opt == '-x': preset = arg
		elif opt == '-n': min_cnt = int(arg)
		elif opt == '-m': min_chain_score = int(arg)
		elif opt == '-r': bw = int(arg)
		elif opt == '-k': k = int(arg)
		elif opt == '-w': w = int(arg)

	a = mp.Aligner(args[0], preset=preset, min_cnt=min_cnt, min_chain_score=min_sc, k=k, w=w, bw=bw)
	if not a: raise Exception("ERROR: failed to load/build index file '{}'".format(args[0]))
	for name, seq, qual in mp.fastx_read(args[1]): # read one sequence
		for h in a.map(seq): # traverse hits
			print('{}\t{}\t{}'.format(name, len(seq), h))

def create_reference_index(reference_panel):
    ## Parse the panel of reference sequences used to find the best match
    panel_aligner = mp.Aligner(reference_panel, best_n = 1)
    if not panel_aligner:
        raise Exception("ERROR: failed to load/build index file '{}'".format(reference_panel))

    reference_panel_names = []
    for name, seq, qual in mp.fastx_read(reference_panel, read_comment=False):
        reference_panel_names.append(name)

    return (panel_aligner, reference_panel_names)

def __init__(self, indexfile, output, output_layout):
        self.aligner = mappy.Aligner(indexfile)
        if not self.aligner:
            raise Exception('Could not open minimap2 index {}.'.format(indexfile))
        self.writers = self.open_writers(indexfile, output, output_layout)