Use pylibcudf only in pure Python mode

python/cudf/cudf/_lib/column.pxd

@@ -7,7 +7,6 @@ from libcpp.memory cimport unique_ptr
 
 from rmm._lib.device_buffer cimport device_buffer
 
-from cudf._lib cimport pylibcudf
 from cudf._lib.cpp.column.column cimport column
 from cudf._lib.cpp.column.column_view cimport column_view, mutable_column_view
 from cudf._lib.cpp.types cimport size_type
@@ -30,7 +29,7 @@ cdef class Column:
     cdef column_view _view(self, size_type null_count) except *
     cdef column_view view(self) except *
     cdef mutable_column_view mutable_view(self) except *
-    cpdef pylibcudf.Column to_pylibcudf(self, mode: Literal["read", "write"])
+    cpdef to_pylibcudf(self, mode: Literal["read", "write"])
 
     @staticmethod
     cdef Column from_unique_ptr(

python/cudf/cudf/_lib/column.pyx

@@ -11,9 +11,6 @@ import rmm
 import cudf
 import cudf._lib as libcudf
 from cudf._lib import pylibcudf
-
-from cudf._lib cimport pylibcudf
-
 from cudf.api.types import is_categorical_dtype, is_datetime64tz_dtype
 from cudf.core.buffer import (
     Buffer,
@@ -447,7 +444,7 @@ cdef class Column:
     # underlying buffers as exposed before this function can itself be exposed
     # publicly.  User requests to convert to pylibcudf must assume that the
     # data may be modified afterwards.
-    cpdef pylibcudf.Column to_pylibcudf(self, mode: Literal["read", "write"]):
+    cpdef to_pylibcudf(self, mode: Literal["read", "write"]):
         """Convert this Column to a pylibcudf.Column.
 
         This function will generate a pylibcudf Column pointing to the same
@@ -477,9 +474,9 @@ cdef class Column:
         else:
             col = self
 
-        cdef pylibcudf.DataType dtype = dtype_to_pylibcudf_type(col.dtype)
+        dtype = dtype_to_pylibcudf_type(col.dtype)
 
-        cdef pylibcudf.gpumemoryview data = None
+        data = None
         if col.base_data is not None:
             cai = cuda_array_interface_wrapper(
                 ptr=col.base_data.get_ptr(mode=mode),
@@ -488,7 +485,7 @@ cdef class Column:
             )
             data = pylibcudf.gpumemoryview(cai)
 
-        cdef pylibcudf.gpumemoryview mask = None
+        mask = None
         if self.nullable:
             # TODO: Are we intentionally use self's mask instead of col's?
             # Where is the mask stored for categoricals?
@@ -587,7 +584,7 @@ cdef class Column:
     #  TODO: Actually support exposed data pointers.
     @staticmethod
     def from_pylibcudf(
-        pylibcudf.Column col, bint data_ptr_exposed=False
+        col, bint data_ptr_exposed=False
     ):
         """Create a Column from a pylibcudf.Column.
 

python/cudf/cudf/_lib/copying.pyx

@@ -11,9 +11,9 @@ from libcpp.vector cimport vector
 from rmm._lib.device_buffer cimport DeviceBuffer
 
 import cudf
+from cudf._lib import pylibcudf
 from cudf.core.buffer import Buffer, acquire_spill_lock, as_buffer
 
-from cudf._lib cimport pylibcudf
 from cudf._lib.column cimport Column
 
 from cudf._lib.scalar import as_device_scalar
@@ -174,7 +174,7 @@ def gather(
     Column gather_map,
     bool nullify=False
 ):
-    cdef pylibcudf.Table tbl = pylibcudf.copying.gather(
+    tbl = pylibcudf.copying.gather(
         pylibcudf.Table([col.to_pylibcudf(mode="read") for col in columns]),
         gather_map.to_pylibcudf(mode="read"),
         pylibcudf.copying.OutOfBoundsPolicy.NULLIFY if nullify

python/cudf/cudf/_lib/types.pxd

@@ -4,7 +4,6 @@ from libc.stdint cimport int32_t
 from libcpp cimport bool
 
 cimport cudf._lib.cpp.types as libcudf_types
-from cudf._lib cimport pylibcudf
 from cudf._lib.cpp.column.column_view cimport column_view
 from cudf._lib.cpp.lists.lists_column_view cimport lists_column_view
 
@@ -18,5 +17,5 @@ ctypedef bool underlying_type_t_null_policy
 cdef dtype_from_column_view(column_view cv)
 
 cdef libcudf_types.data_type dtype_to_data_type(dtype) except *
-cpdef pylibcudf.DataType dtype_to_pylibcudf_type(dtype)
+cpdef dtype_to_pylibcudf_type(dtype)
 cdef bool is_decimal_type_id(libcudf_types.type_id tid) except *

python/cudf/cudf/_lib/types.pyx

@@ -17,7 +17,6 @@ from cudf._lib.types cimport (
 
 import cudf
 from cudf._lib import pylibcudf
-from cudf._lib cimport pylibcudf
 
 size_type_dtype = np.dtype("int32")
 
@@ -257,7 +256,7 @@ cdef libcudf_types.data_type dtype_to_data_type(dtype) except *:
     else:
         return libcudf_types.data_type(tid)
 
-cpdef pylibcudf.DataType dtype_to_pylibcudf_type(dtype):
+cpdef dtype_to_pylibcudf_type(dtype):
     if cudf.api.types.is_list_dtype(dtype):
         return pylibcudf.DataType(pylibcudf.TypeId.LIST)
     elif cudf.api.types.is_struct_dtype(dtype):
@@ -282,7 +281,7 @@ cdef bool is_decimal_type_id(libcudf_types.type_id tid) except *:
     )
 
 
-def dtype_from_pylibcudf_lists_column(pylibcudf.Column col):
+def dtype_from_pylibcudf_lists_column(col):
     child = col.list_view().child()
     tid = child.type().id()
 
@@ -296,15 +295,15 @@ def dtype_from_pylibcudf_lists_column(pylibcudf.Column col):
         )
 
 
-def dtype_from_pylibcudf_structs_column(pylibcudf.Column col):
+def dtype_from_pylibcudf_structs_column(col):
     fields = {
         str(i): dtype_from_pylibcudf_column(col.child(i))
         for i in range(col.num_children())
     }
     return cudf.StructDtype(fields)
 
 
-def dtype_from_pylibcudf_column(pylibcudf.Column col):
+def dtype_from_pylibcudf_column(col):
     type_ = col.type()
     tid = type_.id()
 

python/cudf/cudf/_lib/utils.pxd

@@ -4,7 +4,6 @@ from libcpp.memory cimport unique_ptr
 from libcpp.string cimport string
 from libcpp.vector cimport vector
 
-from cudf._lib cimport pylibcudf
 from cudf._lib.cpp.column.column cimport column_view
 from cudf._lib.cpp.table.table cimport table, table_view
 
@@ -19,4 +18,4 @@ cdef table_view table_view_from_columns(columns) except *
 cdef table_view table_view_from_table(tbl, ignore_index=*) except*
 cdef columns_from_unique_ptr(unique_ptr[table] c_tbl)
 cdef columns_from_table_view(table_view tv, object owners)
-cdef columns_from_pylibcudf_table(pylibcudf.Table table)
+cdef columns_from_pylibcudf_table(tbl)

python/cudf/cudf/_lib/utils.pyx

@@ -11,7 +11,6 @@ from libcpp.string cimport string
 from libcpp.utility cimport move
 from libcpp.vector cimport vector
 
-from cudf._lib cimport pylibcudf
 from cudf._lib.column cimport Column
 from cudf._lib.cpp.column.column cimport column, column_view
 from cudf._lib.cpp.table.table cimport table
@@ -247,7 +246,7 @@ cdef columns_from_unique_ptr(
     return columns
 
 
-cdef columns_from_pylibcudf_table(pylibcudf.Table tbl):
+cdef columns_from_pylibcudf_table(tbl):
     """Convert a pylibcudf table into list of columns.
 
     Parameters
@@ -260,7 +259,6 @@ cdef columns_from_pylibcudf_table(pylibcudf.Table tbl):
     list[Column]
         A list of columns.
     """
-    cdef pylibcudf.Column plc
     return [Column.from_pylibcudf(plc) for plc in tbl.columns()]