Grouping DataFrame based on the limit fails based on PYTHON

Question

i have data set similar to this

Parameter,LL,UL,DATA1,DATA2,DATA3
a,1,5,3,6,2
b,1,3,5,1,2
c,3,5,6,7,2
d,1,4,5,2,4,
e,2,100,45,76,14
f,2,200,23,45,67
g,300,23,