CLN/STY: Nitpicks

pandas/_libs/algos.pyx

@@ -38,8 +38,15 @@ cimport pandas._libs.util as util
 from pandas._libs.util cimport numeric, get_nat
 
 from pandas._libs.khash cimport (
-    khiter_t, kh_destroy_int64, kh_put_int64, kh_init_int64, kh_int64_t,
-    kh_resize_int64, kh_get_int64)
+    kh_destroy_int64,
+    kh_get_int64,
+    kh_init_int64,
+    kh_int64_t,
+    kh_put_int64,
+    kh_resize_int64,
+    khiter_t,
+)
+
 
 import pandas._libs.missing as missing
 
@@ -791,8 +798,13 @@ ctypedef fused rank_t:
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-def rank_1d(rank_t[:] in_arr, ties_method='average',
-            ascending=True, na_option='keep', pct=False):
+def rank_1d(
+    rank_t[:] in_arr,
+    ties_method="average",
+    bint ascending=True,
+    na_option="keep",
+    bint pct=False,
+):
     """
     Fast NaN-friendly version of ``scipy.stats.rankdata``.
     """
@@ -1009,8 +1021,14 @@ def rank_1d(rank_t[:] in_arr, ties_method='average',
         return ranks
 
 
-def rank_2d(rank_t[:, :] in_arr, axis=0, ties_method='average',
-            ascending=True, na_option='keep', pct=False):
+def rank_2d(
+    rank_t[:, :] in_arr,
+    int axis=0,
+    ties_method="average",
+    bint ascending=True,
+    na_option="keep",
+    bint pct=False,
+):
     """
     Fast NaN-friendly version of ``scipy.stats.rankdata``.
     """
@@ -1190,9 +1208,12 @@ ctypedef fused out_t:
 
 @cython.boundscheck(False)
 @cython.wraparound(False)
-def diff_2d(diff_t[:, :] arr,
-            out_t[:, :] out,
-            Py_ssize_t periods, int axis):
+def diff_2d(
+    diff_t[:, :] arr,
+    out_t[:, :] out,
+    Py_ssize_t periods,
+    int axis,
+):
     cdef:
         Py_ssize_t i, j, sx, sy, start, stop
         bint f_contig = arr.is_f_contig()

pandas/_libs/index.pyx

@@ -2,10 +2,19 @@ import warnings
 
 import numpy as np
 cimport numpy as cnp
-from numpy cimport (ndarray, intp_t,
-                    float64_t, float32_t,
-                    int64_t, int32_t, int16_t, int8_t,
-                    uint64_t, uint32_t, uint16_t, uint8_t
+from numpy cimport (
+    float32_t,
+    float64_t,
+    int8_t,
+    int16_t,
+    int32_t,
+    int64_t,
+    intp_t,
+    ndarray,
+    uint8_t,
+    uint16_t,
+    uint32_t,
+    uint64_t,
 )
 cnp.import_array()
 
@@ -364,7 +373,7 @@ cdef class ObjectEngine(IndexEngine):
 
 cdef class DatetimeEngine(Int64Engine):
 
-    cdef _get_box_dtype(self):
+    cdef str _get_box_dtype(self):
         return 'M8[ns]'
 
     cdef int64_t _unbox_scalar(self, scalar) except? -1:
@@ -454,7 +463,7 @@ cdef class DatetimeEngine(Int64Engine):
 
 cdef class TimedeltaEngine(DatetimeEngine):
 
-    cdef _get_box_dtype(self):
+    cdef str _get_box_dtype(self):
         return 'm8[ns]'
 
     cdef int64_t _unbox_scalar(self, scalar) except? -1:

pandas/_libs/indexing.pyx

@@ -2,7 +2,8 @@ cdef class _NDFrameIndexerBase:
     """
     A base class for _NDFrameIndexer for fast instantiation and attribute access.
     """
-    cdef public object obj, name, _ndim
+    cdef public:
+        object obj, name, _ndim
 
     def __init__(self, name, obj):
         self.obj = obj

pandas/_libs/interval.pyx

@@ -1,18 +1,33 @@
 import numbers
 from operator import le, lt
 
-from cpython.object cimport (Py_EQ, Py_NE, Py_GT, Py_LT, Py_GE, Py_LE,
-                             PyObject_RichCompare)
+from cpython.object cimport (
+    Py_EQ,
+    Py_GE,
+    Py_GT,
+    Py_LE,
+    Py_LT,
+    Py_NE,
+    PyObject_RichCompare,
+)
+
 
 import cython
 from cython import Py_ssize_t
 
 import numpy as np
 cimport numpy as cnp
 from numpy cimport (
-    int64_t, int32_t, float64_t, float32_t, uint64_t,
+    NPY_QUICKSORT,
+    PyArray_ArgSort,
+    PyArray_Take,
+    float32_t,
+    float64_t,
+    int32_t,
+    int64_t,
     ndarray,
-    PyArray_ArgSort, NPY_QUICKSORT, PyArray_Take)
+    uint64_t,
+)
 cnp.import_array()
 
 

pandas/_libs/ops.pyx

@@ -1,7 +1,15 @@
 import operator
 
-from cpython.object cimport (PyObject_RichCompareBool,
-                             Py_EQ, Py_NE, Py_LT, Py_LE, Py_GT, Py_GE)
+from cpython.object cimport (
+    Py_EQ,
+    Py_GE,
+    Py_GT,
+    Py_LE,
+    Py_LT,
+    Py_NE,
+    PyObject_RichCompareBool,
+)
+
 
 import cython
 from cython import Py_ssize_t

pandas/_libs/properties.pyx

@@ -1,7 +1,6 @@
 from cython import Py_ssize_t
 
-from cpython.dict cimport (
-    PyDict_Contains, PyDict_GetItem, PyDict_SetItem)
+from cpython.dict cimport PyDict_Contains, PyDict_GetItem, PyDict_SetItem
 
 
 cdef class CachedProperty: