diff --git a/poetry.lock b/poetry.lock
index b3d636d..4958671 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -67,7 +67,7 @@ description = "Disable App Nap on OS X 10.9"
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "sys_platform == \"darwin\""
+marker = "python_version >= \"3.7\" and python_version < \"4.0\" and sys_platform == \"darwin\""
 
 [[package]]
 name = "atomicwrites"
@@ -110,6 +110,7 @@ description = "Specifications for callback functions passed in to an API"
 category = "dev"
 optional = false
 python-versions = "*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "black"
@@ -164,7 +165,7 @@ description = "Cross-platform colored terminal text."
 category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-marker = "sys_platform == \"win32\""
+marker = "python_version >= \"3.7\" and python_version < \"4.0\" and sys_platform == \"win32\" or sys_platform == \"win32\""
 
 [[package]]
 name = "csvkit"
@@ -196,6 +197,7 @@ description = "Decorators for Humans"
 category = "dev"
 optional = false
 python-versions = ">=2.6, !=3.0.*, !=3.1.*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "et-xmlfile"
@@ -241,6 +243,7 @@ description = "IPython: Productive Interactive Computing"
 category = "dev"
 optional = false
 python-versions = ">=3.7"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [package.extras]
 all = ["Sphinx (>=1.3)", "ipykernel", "ipyparallel", "ipywidgets", "nbconvert", "nbformat", "nose (>=0.10.1)", "notebook", "numpy (>=1.14)", "pygments", "qtconsole", "requests", "testpath"]
@@ -273,6 +276,7 @@ description = "Vestigial utilities from IPython"
 category = "dev"
 optional = false
 python-versions = "*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "isodate"
@@ -313,6 +317,7 @@ description = "An autocompletion tool for Python that can be used for text edito
 category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [package.extras]
 qa = ["flake8 (3.7.9)"]
@@ -422,6 +427,7 @@ description = "A Python Parser"
 category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [package.extras]
 testing = ["docopt", "pytest (>=3.0.7)"]
@@ -441,7 +447,7 @@ description = "Pexpect allows easy control of interactive console applications."
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "sys_platform != \"win32\""
+marker = "python_version >= \"3.7\" and python_version < \"4.0\" and sys_platform != \"win32\""
 
 [package.dependencies]
 ptyprocess = ">=0.5"
@@ -453,6 +459,7 @@ description = "Tiny 'shelve'-like database with concurrency support"
 category = "dev"
 optional = false
 python-versions = "*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "pluggy"
@@ -472,6 +479,7 @@ description = "Library for building powerful interactive command lines in Python
 category = "dev"
 optional = false
 python-versions = ">=3.6.1"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [package.dependencies]
 wcwidth = "*"
@@ -483,7 +491,7 @@ description = "Run a subprocess in a pseudo terminal"
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "sys_platform != \"win32\""
+marker = "python_version >= \"3.7\" and python_version < \"4.0\" and sys_platform != \"win32\""
 
 [[package]]
 name = "py"
@@ -524,6 +532,7 @@ description = "Pygments is a syntax highlighting package written in Python."
 category = "dev"
 optional = false
 python-versions = ">=3.5"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "pyparsing"
@@ -717,6 +726,7 @@ description = "Traitlets Python configuration system"
 category = "dev"
 optional = false
 python-versions = ">=3.7"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [package.extras]
 test = ["pytest"]
@@ -760,6 +770,7 @@ description = "Measures the displayed width of unicode strings in a terminal"
 category = "dev"
 optional = false
 python-versions = "*"
+marker = "python_version >= \"3.7\" and python_version < \"4.0\""
 
 [[package]]
 name = "xlrd"
@@ -772,7 +783,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 [metadata]
 lock-version = "1.0"
 python-versions = "^3.8"
-content-hash = "f2b44f7c90405bd10d785485f3b43e1da527e74d3dfdca45d47a6a67be559aa2"
+content-hash = "63f2c6ef09652c4f8407660ff7b4690c8a07e5501eb8fc8c477f485de5888fcf"
 
 [metadata.files]
 agate = [
diff --git a/pyproject.toml b/pyproject.toml
index 435d1b6..076a306 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,7 +19,7 @@ langid = "^1.1.6"
 
 [tool.poetry.dev-dependencies]
 pytest = "^6.1.1"
-ipython = "^7.18.1"
+ipython = { version = "^7.18.1", python = "^3.7" }
 flake8 = "^3.8.4"
 pytest-clarity = "^0.3.0-alpha.0"
 black = "20.8b1"