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
"""
    Returns true if the class is from the package expected.
    :param the_class: the class object
    :param expected_package: package expected for the class
    :return:
    """
    return the_class.__module__.startswith(expected_package)
def inherits_from(the_class: Type, expected_ancestor: Type) -> bool:
    """
    Returns true if the class inherits (directly or indirectly) from the class specified.
    :param the_class: The class to check
    :param expected_ancestor: expected class to inherit from
    :return: true is the class inherits from the class expected
    """
    if expected_ancestor is None:
        return False
    import inspect
    mro = inspect.getmro(the_class)
    return the_class is not expected_ancestor and expected_ancestor in mro
def is_class(the_class: Type) -> bool:
    """
    Returns true if the object passed is a class
    :param the_class: the class to pass
    :return: true if it is a class
    """
    import inspect
    return inspect.isclass(the_class)
def package_name_matches(the_class: Type, expected_pattern: Optional[str]) -> bool: