写一段python代码，使用picosdk的ps4000a，以20000Hz的采样率采集数据

好的，以下是使用picosdk的ps4000a，以20000Hz的采样率采集数据的Python代码：

import time
from picosdk.ps4000a import ps4000a as ps
from picosdk.functions import assert_pico_ok

# 获取设备信息
serial_number = "ABCD1234" # 用实际的设备序列号替换此处
resolution = ps.PS4000A_DEVICE_RESOLUTION["PS4000A_DR_12BIT"]
channels = [ps.Channel.A, ps.Channel.B, ps.Channel.C, ps.Channel.D]

# 打开设备
device = ps.Device()
assert_pico_ok(device.open_unit(), "open_unit")

# 设置采样率和缓冲区大小
sampling_rate = 20000 # 采样率为20000Hz
num_samples = 10000 # 缓冲区大小为10000个采样点

# 配置通道
for channel in channels:
    assert_pico_ok(device.set_channel(channel, enabled=True, coupling=ps.Coupling.DC), f"set_channel({channel})")

# 设置触发条件
assert_pico_ok(device.set_simple_trigger(ps.Channel.A, threshold_V=0.5, direction=ps.Direction.RISING, delay=0, timeout_ms=1000), "set_simple_trigger")

# 开始采集数据
assert_pico_ok(device.set_data_buffer(channels, num_samples), "set_data_buffer")
assert_pico_ok(device.run_block(sampling_rate, num_samples), "run_block")
while device.is_ready() == False:
    time.sleep(0.1)

# 获取数据
data = {}
for channel in channels:
    _, waveform = device.get_data(channel, num_samples)
    data[channel] = waveform

# 显示数据
print(data)

# 关闭设备
device.close_unit()

需要注意的是，以上代码中的serial_number、sampling_rate和num_samples需要根据实际情况进行修改。另外，运行代码前需要先安装picosdk库。