diff --git a/traja/core.py b/traja/core.py
new file mode 100644
index 00000000..ec274fe0
--- /dev/null
+++ b/traja/core.py
@@ -0,0 +1,5 @@
+import pandas as pd
+
+# Check whether pandas series is datetime or timedelta
+def is_datetime_or_timedelta_dtype(series: pd.Series) -> bool:
+    return pd.api.types.is_datetime64_dtype(series) or pd.api.types.is_timedelta64_dtype(series)
\ No newline at end of file
diff --git a/traja/plotting.py b/traja/plotting.py
index 391d75bc..bb9fc6e0 100644
--- a/traja/plotting.py
+++ b/traja/plotting.py
@@ -14,15 +14,14 @@
 from matplotlib.axes import Axes
 from matplotlib.collections import PathCollection
 from matplotlib.figure import Figure
-from mpl_toolkits.mplot3d import Axes3D
 from pandas.core.dtypes.common import (
-    is_datetime_or_timedelta_dtype,
     is_datetime64_any_dtype,
     is_timedelta64_dtype,
 )
 
 import traja
 from traja.frame import TrajaDataFrame
+from traja.core import is_datetime_or_timedelta_dtype
 from traja.trajectory import coords_to_flow
 
 __all__ = [
diff --git a/traja/trajectory.py b/traja/trajectory.py
index 51f672e1..26a4d320 100644
--- a/traja/trajectory.py
+++ b/traja/trajectory.py
@@ -6,7 +6,6 @@
 import numpy as np
 import pandas as pd
 from pandas.core.dtypes.common import (
-    is_datetime_or_timedelta_dtype,
     is_datetime64_any_dtype,
     is_timedelta64_dtype,
 )
@@ -15,6 +14,7 @@
 
 import traja
 from traja import TrajaDataFrame
+from traja.core import is_datetime_or_timedelta_dtype
 
 __all__ = [
     "_bins_to_tuple",