如何使用python将心电信号st段提取出来，请给出代码

以下是一份示例代码，可用于提取心电信号ST段。请注意，这只是一个示例，具体实施取决于特定的数据格式和处理需求。

import wfdb
import numpy as np

# 读取心电文件
record = wfdb.rdrecord('example.ecg', channels=[0])
signal = record.p_signal[:, 0]

# 应用滤波器以去除基线漂移和噪声
from scipy import signal as sig
nyquist = 0.5 * record.fs
low = 0.05 / nyquist
high = 0.5 / nyquist
b, a = sig.butter(1, [low, high], btype='band')
filtered_signal = sig.filtfilt(b, a, signal)

# 检测QRS波峰
from biosppy.signals import ecg
qrs = ecg.qrs.hamilton_segmenter(filtered_signal, record.fs)

# 通过QRS波峰来确定R峰和T峰位置
rpeaks, = ecg.hamilton_segmenter(filtered_signal, record.fs)
templates, rpeaks = ecg.extract_heartbeats(filtered_signal, rpeaks, record.fs)

# 定位ST段
s_point = int(0.2 * record.fs)
t_point = int(0.4 * record.fs)
st_segment = []
for i in range(len(rpeaks)):
    st = templates[i][rpeaks[i]+s_point:rpeaks[i]+t_point]
    st_segment.append(st)
st_segment = np.array(st_segment)