from __future__ import unicode_literals
from __future__ import print_function
from __future__ import division
from __future__ import absolute_import
from future import standard_library
from future.utils import with_metaclass
standard_library.install_aliases()  # NOQA

from abc import ABCMeta
from abc import abstractmethod


class Env(with_metaclass(ABCMeta, object)):
    """RL learning environment.

    This serves a minimal interface for RL agents.
    """

    @abstractmethod
    def step(self, action):
        raise NotImplementedError()

    @abstractmethod
    def reset(self):
        raise NotImplementedError()

    @abstractmethod
    def close(self):
        raise NotImplementedError()


class VectorEnv(with_metaclass(ABCMeta, object)):
    """Parallel RL learning environments."""

    @abstractmethod
    def step(self, action):
        raise NotImplementedError()

    @abstractmethod
    def reset(self, mask):
        raise NotImplementedError()

    @abstractmethod
    def seed(self, seeds):
        raise NotImplementedError()

    @abstractmethod
    def close(self):
        raise NotImplementedError()

@@ -926,16 +926,200 @@
  mask):%0A
+        %22%22%22Reset envs.%0A%0A        Args:%0A            mask (Sequence of bool): Mask array that specifies which env to%0A                skip. If omitted, all the envs are reset.%0A        %22%22%22%0A
         

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