def assert_equals(source_dict, expected_dict):
    """
    Check equality with expected values in dictionary keys.

    Args:
     - source_dict   (dict): the dict containing the keys/values that should
                             conform to expected values
     - expected_dict (dict): the dict containing keys of the `source_dict`, with
                             expected values of those keys as values
    Returns:
     list: empty list if all checks succeeded, list of error message str if
           some checks failed
    """
    error_tplt = "Expected value '{}' for key '{}', got '{}'"

    errors = [
        error_tplt.format(value, key, source_dict.get(key))
        for key, value in expected_dict.items()
        if source_dict.get(key) != value
    ]

    return errors