Pandas drop multiple in range value using isin

Given a df

     a
0    1
1    2
2    1
3    7
4   10
5   11
6   21
7   22
8   26
9   51
10  56
11  83
12  82
13  85
14  90

I would like to drop rows if the value in column a is not within these multiple range
(10-15),(25-30),(50-55), (80-85). Such that these range are made from the ‘lbotandltop`

lbot =[10, 25, 50, 80]
ltop=[15, 30, 55, 85]

I am thinking this can be achieve via pandas isin

df[df['a'].isin(list(zip(lbot,ltop)))]

But, it return empty df instead.

The expected output is

a
10
11
26
51
83
82
85

>Solution :

Create values in flatten list comprehension with range:

df = df[df['a'].isin([z for x, y in zip(lbot,ltop) for z in range(x, y+1)])]
print (df)
     a
4   10
5   11
8   26
9   51
11  83
12  82
13  85

Or use np.concatenate for flatten list of ranges:

df = df[df['a'].isin(np.concatenate([range(x, y+1) for x, y in zip(lbot,ltop)]))]