diff --git a/.github/workflows/commit-ibflex.yml b/.github/workflows/commit-ibflex.yml
index 0e112a8..db8677f 100644
--- a/.github/workflows/commit-ibflex.yml
+++ b/.github/workflows/commit-ibflex.yml
@@ -8,16 +8,16 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.7, 3.8]
+        python-version: ["3.11", "3.12"]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
     # - name: Cache pip
-    #   uses: actions/cache@v2
+    #   uses: actions/cache@v4
     #   with:
     #     path: ~/.cache/pip  # This path is specific to Ubuntu
     #     # Look to see if there is a cache hit for the corresponding requirements file
@@ -29,5 +29,5 @@ jobs:
       run: pip install -r requirements-development.txt
     - name: Static analysis with mypy
       run: mypy ibflex tests
-    - name: Test with nose
-      run: nosetests -dsv --with-coverage --cover-package ibflex tests/*.py
+    - name: Test with pytest
+      run: pytest -v --cov=ibflex tests/
diff --git a/ibflex/Types.py b/ibflex/Types.py
index 7f159e0..80deb5f 100644
--- a/ibflex/Types.py
+++ b/ibflex/Types.py
@@ -468,7 +468,6 @@ class EquitySummaryByReportDateInBase(FlexElement):
     physDel: Optional[decimal.Decimal] = None
     physDelLong: Optional[decimal.Decimal] = None
     physDelShort: Optional[decimal.Decimal] = None
-    currency: Optional[str] = None
     insuredBankDepositRedemptionCashComponentLong: Optional[decimal.Decimal] = None
     insuredBankDepositRedemptionCashComponentShort: Optional[decimal.Decimal] = None
     incentiveCouponAccrualsLong: Optional[decimal.Decimal] = None
@@ -1454,14 +1453,10 @@ class SymbolSummary(FlexElement):
     commodityType: Optional[str] = None
     cost: Optional[decimal.Decimal] = None
     deliveryType: Optional[str] = None
-    exchOrderId: Optional[str] = None
-    extExecID: Optional[str] = None
     fifoPnlRealized: Optional[decimal.Decimal] = None
     fineness: Optional[decimal.Decimal] = None
-    holdingPeriodDateTime: Optional[datetime.datetime] = None
     ibCommission: Optional[decimal.Decimal] = None
     ibCommissionCurrency: Optional[str] = None
-    ibExecID: Optional[str] = None
     ibOrderID: Optional[str] = None
     initialInvestment: Optional[bool] = None
     mtmPnl: Optional[decimal.Decimal] = None
@@ -1469,15 +1464,9 @@ class SymbolSummary(FlexElement):
     netCashInBase: Optional[decimal.Decimal] = None
     notes: Optional[str] = None
     openCloseIndicator: Optional[enums.OpenClose] = None
-    openDateTime: Optional[datetime.datetime] = None
     origOrderID: Optional[str] = None
     rtn: Optional[str] = None
     serialNumber: Optional[str] = None
-    settleDateTarget: Optional[datetime.date] = None
-    taxes: Optional[decimal.Decimal] = None
-    tradeMoney: Optional[decimal.Decimal] = None
-    tradePrice: Optional[decimal.Decimal] = None
-    transactionID: Optional[str] = None
     weight: Optional[str] = None
     whenRealized: Optional[datetime.datetime] = None
     whenReopened: Optional[datetime.datetime] = None
diff --git a/ibflex/parser.py b/ibflex/parser.py
index f582187..6d7107c 100755
--- a/ibflex/parser.py
+++ b/ibflex/parser.py
@@ -12,7 +12,7 @@
 import decimal
 import itertools
 import functools
-from typing import Tuple, Union, Optional, Any, Callable, Iterable
+from typing import Tuple, Union, Optional, Any, Callable, Iterable, cast
 
 from ibflex import Types, enums, utils
 
@@ -107,7 +107,7 @@ def parse(source) -> Types.FlexQueryResponse:
 
 def parse_element(
     elem: ET.Element
-) -> Union[Types.FlexElement, Tuple[Types.FlexElement, ...]]:
+) -> Optional[Union[Types.FlexElement, Tuple[Types.FlexElement, ...]]]:
     """Distinguish XML data element from container element; dispatch accordingly.
 
     Flex format stores data as XML element attributes, while container elements
@@ -150,8 +150,8 @@ def parse_element_container(elem: ET.Element) -> Tuple[Types.FlexElement, ...]:
 
     instances = tuple(parse_data_element(child) for child in elem)
     if _UNKNOWN_ATTRIBUTE_TOLERANCE:
-        instances = tuple(inst for inst in instances if inst is not None)
-    return instances
+        instances = cast(Tuple[Types.FlexElement, ...], tuple(inst for inst in instances if inst is not None))
+    return cast(Tuple[Types.FlexElement, ...], instances)
 
 
 def parse_data_element(
@@ -194,6 +194,7 @@ def parse_data_element(
     if contained_elements:
         assert elem.tag in ("FlexQueryResponse", "FlexStatement")
         if _UNKNOWN_ATTRIBUTE_TOLERANCE:
+            assert known is not None
             #  Filter out unknown or unparseable contained elements
             contained_elements = {
                 k: v for k, v in contained_elements.items()
diff --git a/requirements-development.txt b/requirements-development.txt
index d64e4b0..9b268b5 100644
--- a/requirements-development.txt
+++ b/requirements-development.txt
@@ -8,8 +8,8 @@ requests
 types-requests
 
 # test running
-nose
-coverage
+pytest
+pytest-cov
 pylint
 mypy
 black
diff --git a/setup.cfg b/setup.cfg
index fc1530f..8015f86 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,9 +1,5 @@
-[nosetests]
-verbosity=2
-detailed-errors = 1
-with-coverage = 1
-nocapture = 1
-cover-package = ibflex
+[tool:pytest]
+addopts = -v
 
 [flake8]
 max-line-length = 88