The objective of this Kata is to write a function that creates a dictionary of factors for a range of numbers.

The key for each list in the dictionary should be the number. The list associated with each key should possess the factors for the number.

If a number possesses no factors (only 1 and the number itself), the list for the key should be `['None']`

The function possesses two arguments (`n` and `m`). Where `n` is the starting number and `m` is the ending number.

For example: All factors for 2 (`n`) through to 6 (`m`) with the number being the key in the dictionary:

```python
{2: ['None'], 3: ['None'], 4: [2], 5: ['None'], 6: [2, 3]}
```

Source: codewars | Difficulty: EASY
Tags: Fundamentals

Starter code: def factorsRange(n, m):
	

Solutions:
def factorsRange(n, m):
	return {i: [j for j in range(2, i) if i % j == 0] or ['None'] for i in range(n, m + 1)}


def factorsRange(n, m):
	res = {}
	for num in range(n, m + 1):
		factors = []
		for div in range(2, num // 2 + 1):
			if num % div == 0:
				factors.append(div)
		if len(factors) == 0:
			factors = ['None']
		res[num] = factors
	return res


def factorsRange(n, m):

	def factors(n):
		ret = [i for i in range(2, n) if n % i == 0]
		if not ret:
			return ['None']
		return ret
	return {i: factors(i) for i in range(n, m + 1)}


def factorsRange(n, m):
	(i, dict) = (2, {})
	for num in range(n, m + 1):
		while i < num:
			if num % i == 0 and num != i:
				dict.setdefault(num, []).append(i)
			i += 1
		i = 2
		if num not in dict:
			dict[num] = ['None']
	return dict


LIMIT = 351
memo = [[] for _ in range(LIMIT)]
for x in range(2, LIMIT):
	if not memo[x]:
		memo[x] = ['None']
	for y in range(2 * x, LIMIT, x):
		memo[y].append(x)

def factorsRange(n, m):
	return {i: memo[i] for i in range(n, m + 1)}


from collections import Counter

def factors(n):
	result = set()
	for i in range(2, int(n ** 0.5) + 1):
		if n % i == 0:
			result.add(i)
			result.add(n // i)
	return sorted(result) if result else ['None']

def factorsRange(n, m):
	return {i: factors(i) for i in range(n, m + 1)}


def factorsRange(n, m):
	return {e: [i for i in range(2, round(e / 2) + 1) if not e % i] or ['None'] for e in range(n, m + 1)}


factorsRange = lambda n, m: {x: sorted(set(__import__('itertools').chain(*((y, x / y) for y in range(2, int(x ** 0.5) + 1) if not x % y)))) or ['None'] for x in range(n, m + 1)}


factorsRange = lambda a, b: {n: [d for d in range(2, n) if not n % d] or ['None'] for n in range(a, b + 1)}


def factorsRange(n, m):
	dlist = {}
	for x in range(n, m + 1):
		templist = []
		for y in range(2, x + 1):
			if x % y == 0 and x != y:
				if templist.count(y) == 0:
					templist.append(y)
		if len(templist) >= 1:
			dlist.update({x: templist})
		else:
			dlist.update({x: ['None']})
	return dlist