P4Python does not check out the file in Perforce - python-3.7

Question

I have following piece of code. I'm trying to check out two files from Perforce and put them in a changelist. But run_add does not check the files out. The only thing I see in Perforce is a empty changelist with no files in it.
""" Checks out files from workspace using P4"""
files = ['analyse-location.cfg', 'CMakeLists.txt']
p4 = P4()
# Connect and disconnect
if (p4.connected()):
p4.disconnect()
p4.port = portp4
p4.user = usernameP4
p4.password = passwordP4
p4.client = clientP4
try:
p4.connect()
if p4.connected():
change = p4.fetch_change()
change['Description'] = "Auto"
change['Files'] = []
changeList = p4.save_change(change)[0].split()[1]
for items in files:
abs_path = script_dir + "\\" + items
p4.run_add("-c", changeList, items)
print("Adding file "+ abs_path + " to "+ changeList)
# Done! Disconnect!
p4.disconnect()
except P4Exception:
print("Something went wrong in P4 connection. The errors are: ")
for e in p4.errors:
print(e)
p4.disconnect()
However, when I have instead p4.run("edit", items) it puts the files in the default changelist.It really gets on my nervs. I don't know I am doing that is wrong. The changes list created as well. I use python 3.7 32 bits on Windows

Answer 1

Your script discards the output of the run_add call. Try changing this:
for items in files:
abs_path = script_dir + "\\" + items
p4.run_add("-c", changeList, items)
print("Adding file "+ abs_path + " to "+ changeList)
to:
for items in files:
abs_path = script_dir + "\\" + items
output = p4.run_add("-c", changeList, items)
print("Adding file "+ abs_path + " to "+ changeList)
if output:
print(output)
if p4.errors:
print(p4.errors)
if p4.warnings:
print(p4.warnings)
That will show you the results of the p4 add commands that you're running. Based on the fact that a p4 edit opens the files, I expect you'll find a message like this:
C:\Perforce\test>p4 add foo
//stream/main/foo - can't add existing file
The p4 add and p4 edit commands are not synonymous; one is for adding a new file, one is for editing an existing file. If your script is editing existing files, it should be calling run_edit, not run_add.

Answer 2

I changed my question to following and it worked.
p4.port = portp4
p4.user = usernameP4
p4.password = passwordP4
p4.client = clientP4
try:
p4.connect()
if p4.connected():
change = p4.fetch_change()
change['Description'] = "Auto"
change['Files'] = []
changeList = p4.save_change(change)[0].split()[1]
for items in files:
abs_path = script_dir + "\\" + items
output = p4.run_edit("-c", changeList, items)
print("Adding file "+ abs_path + " to "+ changeList)
if output:
print(output)
if p4.errors:
print(p4.errors)
if p4.warnings:
print(p4.warnings)
p4.disconnect()
except P4Exception:
print("Something went wrong in P4 connection. The errors are: ")
for e in p4.errors:
print(e)
p4.disconnect()
Thanks to #Sam Stafford for his hint. Now it works just like a charm. The key was to change p4.run_add("-c", changelist, items) to p4.run_edit("-c", changelist, items)