Buggy python submission (verdict: Time Limit Exceeded):
M = 1000000007

from fractions import Fraction

N = int(input())

ab_zero_count = 0
a_zero_count = 0
b_zero_count = 0

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	if a == 0 and b == 0:
		ab_zero_count += 1
	elif a == 0:
		a_zero_count += 1
	elif b == 0:
		b_zero_count += 1
	else:
		fish_list.append(Fraction(a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_index_table = {}
for i, (f, c) in enumerate(fish_count_list):
	fish_index_table[(f.numerator, f.denominator)] = i

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	x = -1 / f
	key = (x.numerator, x.denominator)
	if key in fish_index_table:
		j = fish_index_table[key]
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += c

if a_zero_count > 0 and b_zero_count > 0:
	pair_list.append((a_zero_count, b_zero_count))
else:
	singles += a_zero_count + b_zero_count

count = pow(2, singles, M)

#print(singles, pair_list, a_zero_count, b_zero_count)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count += ab_zero_count
count -= 1

print(count % M)


Fixed submission:
M = 1000000007

import math

N = int(input())

ab_zero_count = 0
a_zero_count = 0
b_zero_count = 0

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	if a == 0 and b == 0:
		ab_zero_count += 1
	elif a == 0:
		a_zero_count += 1
	elif b == 0:
		b_zero_count += 1
	else:
		if a < 0:
			a = -a
			b = -b
		g = math.gcd(a, b)
		if g > 1:
			a //= g
			b //= g
		fish_list.append((a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_index_table = {}
for i, (f, c) in enumerate(fish_count_list):
	fish_index_table[f] = i

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	a, b = f
	a, b = (-b, a)
	if a < 0:
		a = -a
		b = -b
	key = (a, b)
	if key in fish_index_table:
		j = fish_index_table[key]
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += c

if a_zero_count > 0 and b_zero_count > 0:
	pair_list.append((a_zero_count, b_zero_count))
else:
	singles += a_zero_count + b_zero_count

count = pow(2, singles, M)

#print(singles, pair_list, a_zero_count, b_zero_count)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count += ab_zero_count
count -= 1

print(count % M)

Buggy python submission (verdict: Time Limit Exceeded):
M = 1000000007

from fractions import Fraction
from bisect import bisect_left

N = int(input())

ab_zero_count = 0
a_zero_count = 0
b_zero_count = 0

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	if a == 0 and b == 0:
		ab_zero_count += 1
	elif a == 0:
		a_zero_count += 1
	elif b == 0:
		b_zero_count += 1
	else:
		fish_list.append(Fraction(a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_count_list.sort()
fish_count_only_list = [f for f, c in fish_count_list]

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	x = -1 / f
	j = bisect_left(fish_count_only_list, x)
	if j != len(fish_count_only_list) and fish_count_only_list[j] == x:
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += c

if a_zero_count > 0 and b_zero_count > 0:
	pair_list.append((a_zero_count, b_zero_count))
else:
	singles += a_zero_count + b_zero_count

count = pow(2, singles, M)

#print(singles, pair_list, a_zero_count, b_zero_count)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count += ab_zero_count
count -= 1

print(count % M)


Fixed submission:
M = 1000000007

import math

N = int(input())

ab_zero_count = 0
a_zero_count = 0
b_zero_count = 0

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	if a == 0 and b == 0:
		ab_zero_count += 1
	elif a == 0:
		a_zero_count += 1
	elif b == 0:
		b_zero_count += 1
	else:
		if a < 0:
			a = -a
			b = -b
		g = math.gcd(a, b)
		if g > 1:
			a //= g
			b //= g
		fish_list.append((a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_index_table = {}
for i, (f, c) in enumerate(fish_count_list):
	fish_index_table[f] = i

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	a, b = f
	a, b = (-b, a)
	if a < 0:
		a = -a
		b = -b
	key = (a, b)
	if key in fish_index_table:
		j = fish_index_table[key]
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += c

if a_zero_count > 0 and b_zero_count > 0:
	pair_list.append((a_zero_count, b_zero_count))
else:
	singles += a_zero_count + b_zero_count

count = pow(2, singles, M)

#print(singles, pair_list, a_zero_count, b_zero_count)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count += ab_zero_count
count -= 1

print(count % M)

Buggy python submission (verdict: Runtime Error):
M = 1000000007

from fractions import Fraction
from bisect import bisect_left

N = int(input())

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	fish_list.append(Fraction(a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_count_list.sort()
fish_count_only_list = [f for f, c in fish_count_list]

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	x = -1 / f
	j = bisect_left(fish_count_only_list, x)
	if j != len(fish_count_only_list) and fish_count_only_list[j] == x:
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += 1

count = pow(2, singles, M)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count -= 1

print(count)


Fixed submission:
M = 1000000007

import math

N = int(input())

ab_zero_count = 0
a_zero_count = 0
b_zero_count = 0

fish_list = []
for _ in range(N):
	a, b = map(int, input().split())
	if a == 0 and b == 0:
		ab_zero_count += 1
	elif a == 0:
		a_zero_count += 1
	elif b == 0:
		b_zero_count += 1
	else:
		if a < 0:
			a = -a
			b = -b
		g = math.gcd(a, b)
		if g > 1:
			a //= g
			b //= g
		fish_list.append((a, b))

#print(fish_list)

fish_table = {}
for f in fish_list:
	if f in fish_table:
		fish_table[f] += 1
	else:
		fish_table[f] = 1

fish_count_list = list(fish_table.items())
fish_index_table = {}
for i, (f, c) in enumerate(fish_count_list):
	fish_index_table[f] = i

#print(fish_count_list)

singles = 0
pair_list = []
checked = [False] * N

for i, (f, c) in enumerate(fish_count_list):
	a, b = f
	a, b = (-b, a)
	if a < 0:
		a = -a
		b = -b
	key = (a, b)
	if key in fish_index_table:
		j = fish_index_table[key]
		if checked[j] == False:
			f2, c2 = fish_count_list[j]
			pair_list.append((c, c2))
			checked[i] = True
	else:
		singles += c

if a_zero_count > 0 and b_zero_count > 0:
	pair_list.append((a_zero_count, b_zero_count))
else:
	singles += a_zero_count + b_zero_count

count = pow(2, singles, M)

#print(singles, pair_list, a_zero_count, b_zero_count)

for c1, c2 in pair_list:
	count = (count * (pow(2, c1, M) + pow(2, c2, M) - 1)) % M

count += ab_zero_count
count -= 1

print(count % M)