Added test case and fix for cython pure python import

isort/core.py

@@ -326,7 +326,10 @@ def process(
                             or " cimport " in import_statement
                             or " cimport*" in import_statement
                             or " cimport(" in import_statement
-                            or ".cimport" in import_statement
+                            or (
+                                ".cimport" in import_statement
+                                and "cython.cimports" not in import_statement
+                            )  # Allow pure python imports. See #2062
                         ):
                             cimport_statement = True
 

tests/unit/test_ticketed_features.py

@@ -1056,3 +1056,20 @@ def test_sort_configurable_sort_issue_1732() -> None:
     )
     with pytest.raises(exceptions.SortingFunctionDoesNotExist):
         isort.code(test_input, sort_order="round")
+
+
+def test_cython_pure_python_imports_2062():
+    """Test to ensure an import form a cython.cimports remains import, not cimport.
+    See: https://github.com/pycqa/isort/issues/2062.
+    """
+    assert isort.check_code(
+        """
+import cython
+from cython.cimports.libc import math
+
+
+def use_libc_math():
+    return math.ceil(5.5)
+""",
+        show_diff=True,
+    )