python client `df.drop` changes input argument

Description

This code:

```
import h2o

h2o.init()
df = h2o.import_file("CreditCard_Cat-train.csv")

dropped = ["PAY_0"]
print(dropped)

df.drop(dropped)
print(dropped)
```

Results in:

```
['PAY_0']
[-7]
```

Which shows that the `dropped` variable has changed after `df.drop` call.

Environment

None

Status

Assignee

New H2O Bugs

Fix versions

None

Reporter

Martin Barus

Support ticket URL

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Priority

Major
Configure