Add requirements.txt with minimum requirements necessary.

Created by: rettigl

I cannot install the package with poetry:

Installing dependencies from lock file
Warning: The lock file is not up to date with the latest changes in pyproject.toml. You may be getting outdated dependencies. Run update to update them.

  SolverProblemError

  Because sed depends on ipykernel (^6.9.1) which doesn't match any versions, version solving failed.

  at /mnt/pcshare/users/Laurenz/AreaB/sed/.pyenv/lib/python3.8/site-packages/poetry/puzzle/solver.py:241 in _solve
      237│             packages = result.packages
      238│         except OverrideNeeded as e:
      239│             return self.solve_in_compatibility_mode(e.overrides, use_latest=use_latest)
      240│         except SolveFailure as e:
    → 241│             raise SolverProblemError(e)
      242│
      243│         results = dict(
      244│             depth_first_search(
      245│                 PackageNode(self._package, packages), aggregate_package_nodes

Also doing a pip -E install results in some dependency problems, it appears because dask is pinned to a specific version:

ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
distributed 2022.2.1 requires dask==2022.02.1, but you have dask 2021.12.0 which is incompatible.

Why is this the case? I would remove any specific version pinning, if not absolutely required.