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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _collapse_preconditions(base_preconditions: List[List[Contract]], bases_have_func: bool, """ Collapse function preconditions with the preconditions collected from the base classes. :param base_preconditions: preconditions collected from the base classes (grouped by base class) :param bases_have_func: True if one of the base classes has the function :param preconditions: preconditions of the function (before the collapse) :param func: function whose preconditions we are collapsing :return: collapsed sequence of precondition groups """

    if not base_preconditions and bases_have_func and preconditions:
        raise TypeError(("The function {} can not weaken the preconditions because the bases specify "
                         "no preconditions at all. Hence this function must accept all possible input since "
                         "the preconditions are OR'ed and no precondition implies a dummy precondition which is always "
                         "fulfilled.").format(func.__qualname__))

    return base_preconditions + preconditions