Continuous dependency conflict with datapackage==1.5.1

[nailend]

I uploaded the new release v0.0.4 to test-pypi to check the installation.
pip install -i https://test.pypi.org/simple/ oemof.tabular

Pip is now throwing the following ERROR and blocks the installation process.

ERROR: Cannot install oemof-tabular==0.0.0, oemof-tabular==0.0.1, oemof-tabular==0.0.3 and oemof-tabular==0.0.4 because these package versions have conflicting dependencies.

The conflict is caused by:
    oemof-tabular 0.0.4 depends on datapackage==1.5.1
    oemof-tabular 0.0.3 depends on datapackage==1.5.1
    oemof-tabular 0.0.1 depends on oemof==0.2.4.dev0
    oemof-tabular 0.0.0 depends on oemof

To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip attempt to solve the dependency conflict

Apparently, this conflict did already exist in version 0.0.3.

This is the specific message for v0.0.4

> pip install -i https://test.pypi.org/simple/ oemof.tabular==0.0.4
Looking in indexes: https://test.pypi.org/simple/
Requirement already satisfied: oemof.tabular==0.0.4 in ./miniconda3/envs/oemof.tabular_v0.0.4_pypi-test/lib/python3.10/site-packages (0.0.4)
INFO: pip is looking at multiple versions of oemof-tabular to determine which version is compatible with other requirements. This could take a while.
ERROR: Could not find a version that satisfies the requirement datapackage==1.5.1 (from oemof-tabular) (from versions: 0.6.0)
ERROR: No matching distribution found for datapackage==1.5.1

I will now check if the version of datapackage can be loosened.
@henhuy do you have any suggestions?

[nailend]

This seems to be a test-pypi problem only as it tries to source all other package from test-pypi as well.