The dependencies in Alphas are currently >= 2.0.0 and should be >=2.0.0a0 in order to work with Alphas in cases which are not PEP 440-compliant.

According to https://www.python.org/dev/peps/pep-0440/, >= 2.0.0 should also work with alpha/beta releases (a1/a2) but in some cases it does not (https://apache-airflow.slack.com/archives/C0146STM600/p1602774750041800) 

Changing to ">=2.0.0a0" should help.
provider_packages/setup_provider_packages.py
moved_entities: Dict[str, str],
                                   full_package_name: str) -> str:
    """
    Converts moved entities to a markdown table
    :param entity_type: type of entities -> operators, sensors etc.
    :param moved_entities: dictionary of moved entities `to -> from`
    :param full_package_name: name of the provider package
    :return: table of moved classes
    """
    from tabulate import tabulate
    headers = [f"Airflow 2.0 {entity_type.value.lower()}: `{full_package_name}` package",
               "Airflow 1.10.* previous location (usually `airflow.contrib`)"]
    table = [
        (get_class_code_link(full_package_name, to_class, "master"),
         get_class_code_link("airflow", moved_entities[to_class], "v1-10-stable"))
        for to_class in sorted(moved_entities.keys())
    ]
    return tabulate(table, headers=headers, tablefmt="pipe")
def get_details_about_classes(