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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _issubclass_Mapping_covariant(subclass, superclass, bound_Generic, bound_typevars, bound_typevars_readonly, follow_fwd_refs, _recursion_check):
 """Helper for _issubclass, a.k.a pytypes.issubtype. This subclass-check treats Mapping-values as covariant. """

    if is_Generic(subclass):
        if subclass.__origin__ is None or not issubclass(subclass.__origin__, Mapping):
            return _issubclass_Generic(subclass, superclass, bound_Generic, bound_typevars,
                    bound_typevars_readonly, follow_fwd_refs, _recursion_check)
        if superclass.__args__ is None:
            if not pytypes.check_unbound_types:
                raise TypeError("Attempted to check unbound mapping type(superclass): "+
                        str(superclass))
            if pytypes.strict_unknown_check:
                # Nothing is subtype of unknown type
                return False
            super_args = (Any, Any)
        else:
            super_args = superclass.__args__
        if subclass.__args__ is None:
            if not pytypes.check_unbound_types:
                raise TypeError("Attempted to check unbound mapping type(subclass): "+
                        str(subclass))
            if pytypes.strict_unknown_check:
                # Nothing can subclass unknown type
                # For value type it would be okay if superclass had Any as value type,
                # as unknown type is subtype of Any. However, since key type is invariant
                # and also unknown, it cannot pass.
                return False
            sub_args = (Any, Any)
        else:
            sub_args = subclass.__args__
        if not _issubclass(sub_args[0], super_args[0],
                bound_Generic, bound_typevars,
                bound_typevars_readonly, follow_fwd_refs, _recursion_check):
            return False
        if not _issubclass(sub_args[1], super_args[1],
                bound_Generic, bound_typevars,
                bound_typevars_readonly, follow_fwd_refs, _recursion_check):
            return False
        return True
    return issubclass(subclass, superclass)