Create a program that will take in a string as input and, if there are duplicates of more than two alphabetical characters in the string, returns the string with all the extra characters in a bracket.

For example, the input "aaaabbcdefffffffg" should return  "aa[aa]bbcdeff[fffff]g" 

Please also ensure that the input is a string, and return "Please enter a valid string" if it is not.

Difficulty: EASY

Starter code:
def string_parse(string):
	

Solutions:
import re

def string_parse(string):
	return re.sub('(.)\\1(\\1+)', '\\1\\1[\\2]', string) if isinstance(string, str) else 'Please enter a valid string'


import re

def string_parse(s):
	if not isinstance(s, str):
		return 'Please enter a valid string'
	for l in set(s):
		s = re.sub('(%s%s)(%s+)' % (l, l, l), '\\1[\\2]', s)
	return s


from functools import partial
from re import compile
REGEX = partial(compile('(.)\\1(\\1+)').sub, '\\1\\1[\\2]')

def string_parse(string):
	return REGEX(string) if type(string) == str else 'Please enter a valid string'


import re

def string_parse(string):
	try:

		def replace(match):
			return '{0}{0}[{1}]'.format(*match.group(1, 2))
		return re.sub('(.)\\1(\\1+)', replace, string)
	except TypeError:
		return 'Please enter a valid string'


from itertools import groupby

def string_parse(string):
	if isinstance(string, str):
		gs = groupby(string)
		f = lambda s: s if len(s) < 3 else s[:2] + '[' + s[2:] + ']'
		return ''.join([f(''.join(list(g))) for (_, g) in groupby(string)])
	else:
		return 'Please enter a valid string'


from itertools import groupby

def string_parse(string):
	return ''.join((f'{x * 2}[{x * (c - 2)}]' if c > 2 else x * c for (x, c) in [(x, len(list(gp))) for (x, gp) in groupby(string)])) if isinstance(string, str) else 'Please enter a valid string'


def string_parse_gen(string):
	(counter, prev_char) = (0, '')
	for char in string:
		if char == prev_char:
			counter += 1
			if counter == 2:
				yield '['
		else:
			if counter >= 2:
				yield ']'
			prev_char = char
			counter = 0
		yield char
	if counter >= 2:
		yield ']'

def string_parse(string):
	return ''.join(list(string_parse_gen(string))) if isinstance(string, str) else 'Please enter a valid string'


def string_parse(s):
	from itertools import groupby
	if not isinstance(s, str):
		return 'Please enter a valid string'
	x = [(i, sum([1 for j in group])) for (i, group) in groupby(s)]
	x = [i[0] * 2 + '[' + i[0] * (i[1] - 2) + ']' if i[1] >= 2 else i[0] for i in x]
	x = ''.join(x)
	x = x.replace('[]', '')
	return x


import re

def string_parse(string):
	if not isinstance(string, str):
		return 'Please enter a valid string'

	def repl(Match):
		s = Match[0]
		n = len(s)
		c = s[0]
		return s if n <= 2 else c * 2 + f'[{c * (n - 2)}]'
	return re.sub('(\\w)\\1*', repl, string)


import re

def string_parse(s):
	try:
		return re.sub('(.)\\1+', lambda m: m.group()[0:2] + '[' + m.group()[2:] + ']' if len(m.group()) > 2 else m.group(), s)
	except TypeError:
		return 'Please enter a valid string'


import re

def string_parse(s):
	return re.sub('((.)\\2*)', lambda x: f'{2 * x[2]}[{x[1][:len(x[1]) - 2]}]' if len(x[1]) > 2 else x[1], s) if isinstance(s, str) else 'Please enter a valid string'


def string_parse(string):
	if not isinstance(string, str):
		return 'Please enter a valid string'
	res = []
	count = 0
	last_char = None
	for c in string:
		if c != last_char:
			if count > 2:
				res.append(']')
			count = 0
		elif count == 2:
			res.append('[')
		count += 1
		last_char = c
		res.append(c)
	if count > 2:
		res.append(']')
	return ''.join(res)


from itertools import groupby

def string_parse(str_in):
	if not isinstance(str_in, str):
		return 'Please enter a valid string'
	str_out = []
	for (_, group) in groupby(str_in):
		s = ''.join(group)
		str_out.append(s if len(s) < 3 else f'{s[:2]}[{s[2:]}]')
	return ''.join(str_out)


def string_parse(string):
	if type(string) != str:
		return 'Please enter a valid string'
	try:
		out = string[:2]
		temp = ''
		for i in string[2:]:
			if i == out[-1] == out[-2]:
				temp += i
			else:
				if temp != '':
					out += '[' + temp + ']'
				out += i
				temp = ''
		if temp != '':
			out += '[' + temp + ']'
		return out
	except:
		return 'Please enter a valid string'


def string_parse(string):
	if not isinstance(string, str):
		return 'Please enter a valid string'
	letters = ['0']
	for i in string:
		if i == letters[-1][-1]:
			letters[-1] += i
		else:
			letters.append(i)
	return ''.join([i if len(i) < 3 else f'{i[:2]}[{i[2:]}]' for i in letters][1:])


import re

def string_parse(string):
	if not type(string) == str:
		return 'Please enter a valid string'
	return re.sub('(([a-zA-Z])\\2)(\\2+)', lambda x: x.group(1) + '[' + x.group(3) + ']', string)


def string_parse(string):
	if string == None or not isinstance(string, str):
		return 'Please enter a valid string'
	if string == '':
		return ''
	res = ''
	current_char = string[0]
	char_counter = 1
	for i in range(1, len(string)):
		if current_char == string[i]:
			if char_counter + 1 <= 2:
				res += current_char
				char_counter += 1
				continue
			elif char_counter + 1 == 3:
				res = res + current_char + '['
				char_counter += 1
				continue
			elif char_counter + 1 > 3:
				res += current_char
				char_counter += 1
		else:
			if char_counter > 2:
				res = res + current_char + ']'
			else:
				res += current_char
			current_char = string[i]
			char_counter = 1
	res = res + current_char if char_counter <= 2 else res + current_char + ']'
	return res


import re

def string_parse(string):
	if type(string) != str:
		return 'Please enter a valid string'
	for c in 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ':
		string = re.sub(c + '{2}(' + c + '+)', c * 2 + '[\\g<1>]', string)
	return string


def string_parse(string):
	if not isinstance(string, str):
		return 'Please enter a valid string'
	if len(string) == 0:
		return ''
	Di = {}
	text = ''
	f = 0
	i = 0
	f2 = 0
	for i in range(len(string) - 1):
		Di.setdefault(string[i], 0)
		text += string[i]
		Di[string[i]] += 1
		if not f and Di[string[i]] >= 2 and (string[i] == string[i + 1]):
			text += '['
			f = 1
		if f and Di[string[i]] >= 2 and (string[i] != string[i + 1]):
			text += ']'
			f = 0
			f2 = 1
		if not f and string[i] != string[i + 1]:
			Di[string[i]] = 0
	text += string[-1]
	if f:
		text += ']'
	return text