Question

Please code in Python

Revise the AbstractBag class so that it behaves as a subclass of AbstractCollection provided in the file abstractcollection.py.

Abstractcollection.py code:

class AbstractCollection(object):

    """An abstract collection implementation."""

    # Constructor

    def __init__(self, sourceCollection = None):

        """Sets the initial state of self, which includes the

        contents of sourceCollection, if it's present."""

        self.size = 0

        if sourceCollection:

            for item in sourceCollection:

                self.add(item)

    # Accessor methods

    def isEmpty(self):

        """Returns True if len(self) == 0, or False otherwise."""

        return len(self) == 0

    

    def __len__(self):

        """Returns the number of items in self."""

        return self.size

    def __str__(self):

        """Returns the string representation of self."""

        return "[" + ", ".join(map(str, self)) + "]"

    def __add__(self, other):

        """Returns a new bag containing the contents

        of self and other."""

        result = type(self)(self)

        for item in other:

            result.add(item)

        return result

    def __eq__(self, other):

        """Returns True if self equals other,

        or False otherwise."""

        if self is other: return True

        if type(self) != type(other) or \

           len(self) != len(other):

            return False

        otherIter = iter(other)

        for item in self:

            if item != next(otherIter):

                return False

        return True

    def count(self, item):

        """Returns the number of instances of item in self."""

        total = 0

        for nextItem in self:

            if nextItem == item:

                total += 1

        return total

Abstractbag.py Code:

from abstractcollection import AbstractCollection

class AbstractBag(AbstractCollection):

    """An abstract bag implementation."""

    # Constructor

    def __init__(self, sourceCollection = None):

        AbstractCollection__init__(self, sourceColletion)

        """Sets the initial state of self, which includes the

        contents of sourceCollection, if it's present."""

        self.size = 0

        if sourceCollection:

            for item in sourceCollection:

                self.add(item)

    # Accessor methods

    def isEmpty(self):

        """Returns True if len(self) == 0, or False otherwise."""

        return len(self) == 0

    def __len__(self):

        """Returns the number of items in self."""

        return self.size

    def __str__(self):

        """Returns the string representation of self."""

        return "{" + ", ".join(map(str, self)) + "}"

    def __add__(self, other):

        """Returns a new bag containing the contents

        of self and other."""

        result = type(self)(self)

        for item in other:

            result.add(item)

        return result

    def __eq__(self, other):

        """Returns True if self equals other,

        or False otherwise."""

        if self is other: return True

        if type(self) != type(other) or \

           len(self) != len(other):

            return False

        for item in self:

            if self.count(item) != other.count(item):

                return False

        return True

    def count(self, item):

        """Returns the number of instances of item in self."""

        total = 0

        for nextItem in self:

            if nextItem == item:

                total += 1

        return total

Answer 1

# do comment if any problem arises

# Code

from abstractcollection import AbstractCollection

class AbstractBag(AbstractCollection):

    """An abstract bag implementation."""

    # Constructor

    def __init__(self, sourceCollection=None):

        super().__init__(sourceCollection=sourceCollection)

    # Accessor methods

    def isEmpty(self):

        """Returns True if len(self) == 0, or False otherwise."""

        return super().isEmpty()

    def __len__(self):

        """Returns the number of items in self."""

        return super().__len__()

    def __str__(self):

        """Returns the string representation of self."""

        return super().__str__()

    def __add__(self, other):

        """Returns a new bag containing the contents

        of self and other."""

        return super().__add__(other)

    def __eq__(self, other):

        """Returns True if self equals other,

        or False otherwise."""

        return super().__eq__(other)

    def count(self, item):

        """Returns the number of instances of item in self."""

        return super().count(item)

Screenshot: