[Python] How can I modify a .tdms file using Python?

I have a .tdms file of a measurement with some faulty data. In group_name = "Tracking data", the channel_name = "Shift (mm)" is filled with gibberish.

Therefore I want to replace the data in "Shift (mm)", while keeping the rest of the file intact as is. As I know nothing about LabView, I wanted to do this in Python using the module npTDMS.

I tried to implement the following function that correctly writes the "Shift (mm)" into a new .tdms file, overwriting my input file :

from nptdms import TdmsFile, TdmsWriter, RootObject, GroupObject, ChannelObject
import numpy as np

# File paths
tdms_file_path = r"P:\My Documents\Images tweezer\data_011.tdms"
replacement_file_path = r"Y:\Gert-Jan\Tweezer data\220407\shift.txt"

# Group and channel details
group_name = "Tracking data"
channel_name = "Shift (mm)"

# Load the replacement data
replacement_data = np.loadtxt(replacement_file_path)

# Write a new .tdms file containing the correct shift derived from replacement data
with TdmsWriter(tdms_file_path) as tdms_writer:
data_array = replacement_data
channel = ChannelObject(group_name, channel_name, data_array)
tdms_writer.write_segment([channel])


I tried to modify this function into something that would retain the original data, using the following script (not working):

from nptdms import TdmsFile, TdmsWriter, RootObject, GroupObject, ChannelObject
import numpy as np

# File paths
tdms_file_path = r"P:\My Documents\Images tweezer\data_011.tdms"
replacement_file_path = r"Y:\Gert-Jan\Tweezer data\220407\shift.txt"
copy_tdms_file_path = r"P:\My Documents\Images tweezer\data_01_copy.tdms"

# Group and channel details
group_name = "Tracking data"
channel_name = "Shift (mm)"

# Load the replacement data
replacement_data = np.loadtxt(replacement_file_path)

# Original datafile properties
original_file = TdmsFile(tdms_file_path)
original_groups = original_file.groups()
original_channels = [chan for group in original_groups for chan in group.channels()]


# Write a new .tdms file containing the shift derived from replacement data
with TdmsWriter(copy_tdms_file_path) as copied_file:
root_object = RootObject(original_file.properties)
channels_to_copy = [chan for chan in original_channels if not chan("Shift (mm)")]
data_array = replacement_data
channel = ChannelObject(group_name, channel_name, data_array)
copied_file.write_segment([root_object] + original_groups + channels_to_copy + [channel])


I have tried many variations of the last part of the code. All run into seemingly unrelated errors or do not produce the correct output file. Does someone know how to implement what I want to do in a correct way?

A similar question has been asked here: Add channels to / edit existing tdms files?, but there is no answer for Python.

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