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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 rand(x_bounds, x_types, lowerbound, upperbound, max_retries=100):
    '''
    Key idea is that we try to move towards upperbound, by randomly choose one
    value for each parameter. However, for the last parameter,
    we need to make sure that its value can help us get above lowerbound
    '''
    outputs = None

    if check_feasibility(x_bounds, lowerbound, upperbound) is True:
        # Order parameters by their range size. We want the smallest range first,
        # because the corresponding parameter has less numbers to choose from
        x_idx_sorted = []
        for i, _ in enumerate(x_bounds):
            if x_types[i] == "discrete_int":
                x_idx_sorted.append([i, len(x_bounds[i])])
            elif (x_types[i] == "range_int") or (x_types[i] == "range_continuous"):
                x_idx_sorted.append([i, math.floor(x_bounds[i][1] - x_bounds[i][0])])
        x_idx_sorted = sorted(x_idx_sorted, key=itemgetter(1))

        for _ in range(max_retries):
            budget_allocated = 0
            outputs = [None] * len(x_bounds)

            for i, _ in enumerate(x_idx_sorted):
                x_idx = x_idx_sorted[i][0]
                # The amount of unallocated space that we have
                budget_max = upperbound - budget_allocated
                # NOT the Last x that we need to assign a random number
                if i < (len(x_idx_sorted) - 1):
                    if x_bounds[x_idx][0] <= budget_max:
                        if x_types[x_idx] == "discrete_int":
                            # Note the valid integer
                            temp = []
                            for j in x_bounds[x_idx]:
                                if j <= budget_max:
                                    temp.append(j)
                            # Randomly pick a number from the integer array
                            if temp:
                                outputs[x_idx] = temp[random.randint(0, len(temp) - 1)]

                        elif (x_types[x_idx] == "range_int") or \
                                    (x_types[x_idx] == "range_continuous"):
                            outputs[x_idx] = random.randint(x_bounds[x_idx][0],
                                                            min(x_bounds[x_idx][-1], budget_max))

                else:
                    # The last x that we need to assign a random number
                    randint_lowerbound = lowerbound - budget_allocated
                    randint_lowerbound = 0 if randint_lowerbound < 0 else randint_lowerbound

                    # This check:
                    # is our smallest possible value going to overflow the available budget space,
                    # and is our largest possible value going to underflow the lower bound
                    if (x_bounds[x_idx][0] <= budget_max) and \
                            (x_bounds[x_idx][-1] >= randint_lowerbound):
                        if x_types[x_idx] == "discrete_int":
                            temp = []
                            for j in x_bounds[x_idx]:
                                # if (j <= budget_max) and (j >= randint_lowerbound):
                                if randint_lowerbound <= j <= budget_max:
                                    temp.append(j)
                            if temp:
                                outputs[x_idx] = temp[random.randint(0, len(temp) - 1)]
                        elif (x_types[x_idx] == "range_int") or \
                                (x_types[x_idx] == "range_continuous"):
                            outputs[x_idx] = random.randint(randint_lowerbound,
                                                            min(x_bounds[x_idx][1], budget_max))
                if outputs[x_idx] is None:
                    break
                else:
                    budget_allocated += outputs[x_idx]
            if None not in outputs:
                break
    return outputs