@property
    def a_interval(self):
        a_interval = []
        for element in self.psets:
            a_interval.append(element.args[0])

        a_interval = Union(*a_interval)
        return a_interval
Return the union of intervals of `x` when, self is in
dataset/ETHPy150Open sympy/sympy/sympy/sets/fancysets.py/ComplexRegion.a_interval