# Path: ndd/exceptions.py
# class NddError(Exception):
#     """Base class for ndd exceptions."""


import collections
import collections.abc
import numbers
import numpy
from types import GeneratorType
from ndd.exceptions import NddError
    from pandas import DataFrame, Series
    from bounter import bounter
            values.append(k)

        return keys, values

    def __len__(self):
        return len(self.statistics)

    def __iter__(self):
        return iter(self.statistics)

    def __contains__(self, key):
        return key in self.statistics

    def __bool__(self):
        return self.data

    def __setitem__(self, key, value):
        """Set item on mapping."""
        self.statistics[key] = value

    def __delitem__(self, key):
        """Delete item from mapping."""
        try:
            del self.statistics[key]
        except KeyError:
            raise KeyError('Key not found in mapping: {!r}'.format(key))

    def popitem(self):
        """Remove and return an item pair from mapping.
        Raise KeyError is data is empty."""

# Path: ndd/exceptions.py
# class NddError(Exception):
#     """Base class for ndd exceptions."""


# Path: ndd/counters.py
import collections
import collections.abc
import numbers
import numpy
from types import GeneratorType
from ndd.exceptions import NddError
    from pandas import DataFrame, Series
    from bounter import bounter

            values.append(k)

        return keys, values

    def __len__(self):
        return len(self.statistics)

    def __iter__(self):
        return iter(self.statistics)

    def __contains__(self, key):
        return key in self.statistics

    def __bool__(self):
        return self.data

    def __setitem__(self, key, value):
        """Set item on mapping."""
        self.statistics[key] = value

    def __delitem__(self, key):
        """Delete item from mapping."""
        try:
            del self.statistics[key]
        except KeyError:
            raise KeyError('Key not found in mapping: {!r}'.format(key))

    def popitem(self):
        """Remove and return an item pair from mapping.
        Raise KeyError is data is empty."""

        try: