d=[['7500', '3.2900', '0', 'apple'],['7500', '-0.3500', '1', 'orange'],['7500', '-4.1400', '2', 'orange'],['7501', '3.4625', '0', 'apple'],['7501', '-0.2275', '1', 'apple'],['7501', '-4.1175', '2', 'orange'],['7502', '3.2087', '0', 'orange'],['7502', '-0.7313', '1', 'apple'],['7502', '-4.7513', '2', 'apple']]
df=pd.DataFrame(d, columns=["Frame","Z","Order","Name"])


>>> df
    Frame       Z   Order   Name
0   7500     3.2900 0   apple
1   7500    -0.3500 1   orange
2   7500    -4.1400 2   orange
3   7501     3.4625 0   apple
4   7501    -0.2275 1   apple
5   7501    -4.1175 2   orange
6   7502     3.2087 0   orange
7   7502    -0.7313 1   apple
8   7502    -4.7513 2   apple

(0,1)
(0,2)
(1,2)

(apple, orange)
(apple, orange)
(orange, orange)

( 3.2900, -0.3500)
( 3.2900, -4.1400)
(-0.3500, -4.1400)

(apple, orange)
first_vals = [3.2900, 3.2900, ...]
second_vals = [-0.3500, -4.1400, ...]

(orange, orange)
first_vals = [-0.3500, ...]
second_vals = [-4.140, ...]

from itertools import combinations
from collections import defaultdict

zpairs = defaultdict(list)

for name, group in df.groupby(["Frame"]):
    order_pairs = combinations(range(len(group)), 2)
    zvals = group["Z"].values
    rowids = group["Name"].values
    for pair in order_pairs:
        pair_str = str(rowids[pair[0]])+"-"+str(rowids[pair[1]])
        zpairs[pair_str+"-first"].append(zvals[pair[0]])
        zpairs[pair_str+"-second"].append(zvals[pair[1]])

>>> dict(zpairs)

{'apple-apple-first': ['3.4625', '-0.7313'],
'apple-apple-second': ['-0.2275', '-4.7513'],
'apple-orange-first': ['3.2900', '3.2900', '3.4625', '-0.2275'],
'apple-orange-second': ['-0.3500', '-4.1400', '-4.1175', '-4.1175'],
'orange-apple-first': ['3.2087', '3.2087'],
'orange-apple-second': ['-0.7313', '-4.7513'],
'orange-orange-first': ['-0.3500'],
'orange-orange-second': ['-4.1400']}