#### Prime Check

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```"""Prime Check."""

import math
import unittest

def prime_check(number: int) -> bool:
"""Checks to see if a number is a prime in O(sqrt(n)).

A number is prime if it has exactly two factors: 1 and itself.

>>> prime_check(0)
False
>>> prime_check(1)
False
>>> prime_check(2)
True
>>> prime_check(3)
True
>>> prime_check(27)
False
>>> prime_check(87)
False
>>> prime_check(563)
True
>>> prime_check(2999)
True
>>> prime_check(67483)
False
"""

if 1 < number < 4:
# 2 and 3 are primes
return True
elif number < 2 or not number % 2:
# Negatives, 0, 1 and all even numbers are not primes
return False

odd_numbers = range(3, int(math.sqrt(number) + 1), 2)
return not any(not number % i for i in odd_numbers)

class Test(unittest.TestCase):
def test_primes(self):
self.assertTrue(prime_check(2))
self.assertTrue(prime_check(3))
self.assertTrue(prime_check(5))
self.assertTrue(prime_check(7))
self.assertTrue(prime_check(11))
self.assertTrue(prime_check(13))
self.assertTrue(prime_check(17))
self.assertTrue(prime_check(19))
self.assertTrue(prime_check(23))
self.assertTrue(prime_check(29))

def test_not_primes(self):
self.assertFalse(
prime_check(-19),
"Negative numbers are excluded by definition of prime numbers.",
)
self.assertFalse(
prime_check(0),
"Zero doesn't have any positive factors, primes must have exactly two.",
)
self.assertFalse(
prime_check(1),
"One only has 1 positive factor, primes must have exactly two.",
)
self.assertFalse(prime_check(2 * 2))
self.assertFalse(prime_check(2 * 3))
self.assertFalse(prime_check(3 * 3))
self.assertFalse(prime_check(3 * 5))
self.assertFalse(prime_check(3 * 5 * 7))

if __name__ == "__main__":
unittest.main()
```