Couldn’t loading `DuckDuckGeese` and `Handwritting`

Describe the bug
DuckDuckDuckGeese and Handwritting cannot be loaded by tslearn.datasets.UCR_UEA_datasets.load_dataset .

To Reproduce

DuckDuckDuckGeese

from tslearn.datasets import UCR_UEA_datasets
loader = UCR_UEA_datasets()
X_train, y_train, X_test, y_test = loader.load_dataset("DuckDuckGeese")

print(type(X_train))    # None

ls /home/user/.tslearn/datasets/UCR_UEA/DuckDuckGeese/DuckDuckGeese
DuckDuckGeese.arff		       DuckDuckGeeseDimension395_TRAIN.arff
DuckDuckGeese.jpg		       DuckDuckGeeseDimension396_TEST.arff
DuckDuckGeese.txt		       DuckDuckGeeseDimension396_TRAIN.arff
DuckDuckGeeseDimension1000_TEST.arff   DuckDuckGeeseDimension397_TEST.arff
....

Handwritting

loader = UCR_UEA_datasets()
X_train, y_train, X_test, y_test = loader.load_dataset("Handwritting")
print(X_train)    # None

ls /root/.tslearn/datasets/UCR_UEA/Handwritting/
None

Expected behavior
I was expecting to get the training and evaluation data corresponding to the specified dataset names.

Environment (please complete the following information):

I used Kaggle's Python Notebook environment as of 08/12/2020.

• OS: Ubuntu 18.04.4
• tslearn version '0.4.1'

Additional context
Apparently, I was able to download the DuckDuckGeese dataset itself.
Handwritting, on the other hand, appears to be failing to download. The directory is created, but its contents are empty.

Start with tslearn.datasets.UCR_UEA_datasets.load_dataset and reproduce the DuckDuckGeese and Handwritting cases from the issue. Inspect how each dataset is downloaded and located, then verify that both calls return training and evaluation arrays rather than None or an empty directory. No specific source file or test is named in the report.