1import re
  2import random
  3
  4
  5class Kid(type):
  6    """Represents a dynamic metaclass for kid with instance tracking."""
  7
  8    _all_instances = {}
  9
 10    def __new__(cls, name, bases, dict):
 11        """Create a new class type."""
 12        if '__call__' not in dict:
 13            raise NotImplementedError(f'Class {name} should implement __call__!')
 14
 15        dict['instances'] = {}
 16        return type.__new__(cls, name, bases, dict)
 17
 18    def __call__(cls, *args, **kwargs):
 19        """Create an instances and tracking them by their ID."""
 20        instance = super(Kid, cls).__call__(*args, **kwargs)
 21        instance_id = id(instance)
 22        instance.years = 0
 23        instance.id = instance_id
 24        instance.is_naughty = False
 25
 26        for attr_name in dir(instance):
 27            if not attr_name.startswith('_'):  # Public methods
 28                attr = getattr(instance, attr_name)
 29                if callable(attr):
 30                    wrapped_method = Kid._wrap_method(attr, instance)
 31                    setattr(instance, attr_name, wrapped_method)
 32
 33        cls.instances[instance_id] = instance
 34        Kid._all_instances[instance_id] = instance
 35        return instance
 36
 37    @staticmethod
 38    def _wrap_method(method, instance):
 39        """Wrap a method to catch exceptions and mark the instance as naughty."""
 40        def wrapped(*args, **kwargs):
 41            try:
 42                return method(*args, **kwargs)
 43            except:
 44                instance.is_naughty = True
 45                raise
 46
 47        return wrapped
 48
 49    @classmethod
 50    def kids_grow(cls):
 51        """All kids grow with one passed year."""
 52        for kid_id, kid in Kid._all_instances.items():
 53            kid.years += 1
 54
 55    @classmethod
 56    def gift_presents(cls, kids_requests, most_wanted):
 57        """Gift presents to all kids."""
 58        for kid_id, kid in Kid._all_instances.items():
 59
 60            if kid.is_naughty:
 61                kid('coal')
 62                kid.is_naughty = False
 63                continue
 64            if kid.years > 5:
 65                Kid._all_instances.pop(kid_id)
 66                continue
 67
 68            if kid_id in kids_requests:
 69                kid(kids_requests[kid_id])
 70            else:
 71                kid(most_wanted)
 72
 73
 74class Santa(object):
 75    """Represents an abstract Santa class."""
 76
 77    def __new__(cls):
 78        """Create a new singleton instance of Santa."""
 79        if not hasattr(cls, '_instance'):
 80            cls._instance = super(Santa, cls).__new__(cls)
 81
 82            cls._instance.kids_requests = {}
 83            cls._instance.wishlist = {}
 84
 85        return cls._instance
 86
 87    def __call__(self, kid, wish):
 88        """Kid calls for a Christmas present wish."""
 89        match = re.search(r'["\']([a-zA-Z0-9 ]+)["\']', wish)
 90        if match:
 91            gift = match.group(1)
 92            self.kids_requests[id(kid)] = gift
 93            self._add_gift_to_wishlist(gift)
 94
 95    def __matmul__(self, letter):
 96        """Kid writes a letter with a Christmas present wish."""
 97        # id_match = re.search(r'^\s*\d+\s*$', letter)
 98        id_match = re.search(r'\s*(\d+)\s*', letter)
 99        gift_match = re.search(r'["\']([a-zA-Z0-9 ]+)["\']', letter)
100
101        if gift_match and id_match:
102            gift = gift_match.group(1)
103            kid_id = int(id_match.group(0))
104
105            self.kids_requests[kid_id] = gift
106            self._add_gift_to_wishlist(gift)
107
108    def __iter__(self):
109        """Iterate over requests of kids."""
110        return iter(self.kids_requests.values())
111
112    def xmas(self):
113        """Take presents to the kids method."""
114        if self.kids_requests and self.wishlist:
115            # max_key = max(self.wishlist, key=self.wishlist.get)
116            max_key = Santa._get_most_wanted_present(self.wishlist)
117            Kid.gift_presents(self.kids_requests, max_key)
118            self.kids_requests.clear()
119            self.wishlist.clear()
120
121        Kid.kids_grow()
122
123    def _add_gift_to_wishlist(self, gift):
124        """Help method for adding to Santa's wishes."""
125        if gift not in self.wishlist:
126            self.wishlist[gift] = 1
127        else:
128            self.wishlist[gift] += 1
129
130    @staticmethod
131    def _get_most_wanted_present(wishlist):
132        """Get random present wish of most wanted present."""
133        max_value = max(wishlist.values())
134        max_keys = [key for key, value in wishlist.items() if value == max_value]
135        random_max_key = random.choice(max_keys)  # Chooses random from list with the same value
136
137        return random_max_key