diff --git a/scripts/build_spec.py b/scripts/build_spec.py
index 4213c38b6..1091e7bed 100644
--- a/scripts/build_spec.py
+++ b/scripts/build_spec.py
@@ -19,6 +19,13 @@ PHASE0_IMPORTS = '''from typing import (
     Tuple,
 )
 
+from dataclasses import (
+    dataclass,
+    field,
+)
+
+from copy import deepcopy
+
 from eth2spec.utils.ssz.ssz_impl import (
     hash_tree_root,
     signing_root,
@@ -44,6 +51,13 @@ PHASE1_IMPORTS = '''from typing import (
     Tuple,
 )
 
+from dataclasses import (
+    dataclass,
+    field,
+)
+
+from copy import deepcopy
+
 from eth2spec.utils.ssz.ssz_impl import (
     hash_tree_root,
     signing_root,
diff --git a/scripts/function_puller.py b/scripts/function_puller.py
index 303d4ec2f..776fcfa82 100644
--- a/scripts/function_puller.py
+++ b/scripts/function_puller.py
@@ -29,6 +29,7 @@ def get_spec(file_name: str) -> SpecObject:
     inserts = {}
     function_matcher = re.compile(FUNCTION_REGEX)
     inserts_matcher = re.compile(BEGIN_INSERT_REGEX)
+    is_ssz = False
     for linenum, line in enumerate(open(file_name).readlines()):
         line = line.rstrip()
         if pulling_from is None and len(line) > 0 and line[0] == '#' and line[-1] == '`':
diff --git a/specs/core/0_fork-choice.md b/specs/core/0_fork-choice.md
index f3d57feaa..1a1465d25 100644
--- a/specs/core/0_fork-choice.md
+++ b/specs/core/0_fork-choice.md
@@ -58,7 +58,8 @@ The head block root associated with a `store` is defined as `get_head(store)`. A
 #### `Target`
 
 ```python
-class Target(Container):
+@dataclass
+class Target(object):
     epoch: Epoch
     root: Bytes32
 ```
@@ -66,13 +67,14 @@ class Target(Container):
 #### `Store`
 
 ```python
-class Store(Container):
-    blocks: Dict[Bytes32, BeaconBlock]
-    states: Dict[Bytes32, BeaconState]
-    time: uint64
-    latest_targets: Dict[ValidatorIndex, Target]
-    justified_root: Bytes32
-    finalized_root: Bytes32
+@dataclass
+class Store(object):
+    blocks: Dict[Bytes32, BeaconBlock] = field(default_factory=dict)
+    states: Dict[Bytes32, BeaconState] = field(default_factory=dict)
+    time: int = 0
+    latest_targets: Dict[ValidatorIndex, Target] = field(default_factory=dict)
+    justified_root: Bytes32 = ZERO_HASH
+    finalized_root: Bytes32 = ZERO_HASH
 ```
 
 ### Helpers
@@ -139,7 +141,7 @@ def on_block(store: Store, block: BeaconBlock) -> None:
     # Check block is a descendant of the finalized block
     assert get_ancestor(store, signing_root(block), store.blocks[store.finalized_root].slot) == store.finalized_root
     # Check block slot against Unix time
-    pre_state = store.states[block.parent_root].copy()
+    pre_state = deepcopy(store.states[block.parent_root])
     assert store.time >= pre_state.genesis_time + block.slot * SECONDS_PER_SLOT
     # Check the block is valid and compute the post-state
     state = state_transition(pre_state, block)
diff --git a/test_libs/pyspec/eth2spec/utils/ssz/ssz_typing.py b/test_libs/pyspec/eth2spec/utils/ssz/ssz_typing.py
index 3bd7dd062..d4b481ef2 100644
--- a/test_libs/pyspec/eth2spec/utils/ssz/ssz_typing.py
+++ b/test_libs/pyspec/eth2spec/utils/ssz/ssz_typing.py
@@ -1,11 +1,9 @@
-import copy
 from typing import (
     List,
     Iterable,
     TypeVar,
     Type,
     NewType,
-    Dict,
     Union,
 )
 from typing_inspect import get_origin
@@ -132,9 +130,6 @@ class Container(object):
         cls = self.__class__
         return [getattr(self, field) for field in cls.get_field_names()]
 
-    def copy(self):
-        return copy.deepcopy(self)
-
     def __repr__(self):
         return repr({field: getattr(self, field) for field in self.get_field_names()})
 
@@ -418,8 +413,6 @@ def get_zero_value(typ):
         return b''
     elif is_container_type(typ):
         return typ(**{f: get_zero_value(t) for f, t in typ.get_fields()})
-    elif is_dict_type(typ):
-        return dict()
     else:
         raise Exception("Type not supported: {}".format(typ))
 
@@ -511,13 +504,6 @@ def is_container_type(typ):
     return isinstance(typ, type) and issubclass(typ, Container)
 
 
-def is_dict_type(typ):
-    """
-    Check of the given type is a Dict. (Which are a part of the super-secret undocumented SSZ spec)
-    """
-    return get_origin(typ) is Dict or get_origin(typ) is dict
-
-
 T = TypeVar('T')
 L = TypeVar('L')
 
diff --git a/test_libs/pyspec/requirements.txt b/test_libs/pyspec/requirements.txt
index 3b38930bd..18e5d2a4c 100644
--- a/test_libs/pyspec/requirements.txt
+++ b/test_libs/pyspec/requirements.txt
@@ -3,3 +3,4 @@ eth-typing>=2.1.0,<3.0.0
 pycryptodome==3.7.3
 py_ecc>=1.6.0
 typing_inspect==0.4.0
+dataclasses==0.6