Fix flake8 errors.

Author: Red-M

ssh2/c_ssh2.pxd

@@ -66,7 +66,6 @@ cdef extern from "libssh2.h" nogil:
         LIBSSH2_FLAG_SIGPIPE
         LIBSSH2_FLAG_COMPRESS
 
-    # ctypedef LIBSSH2_USERAUTH_KBDINT_RESPONSE_FUNC "LIBSSH2_USERAUTH_KBDINT_RESPONSE_FUNC"
     # ctypedef libssh2_uint64_t libssh2_struct_stat_size
     ctypedef struct libssh2_struct_stat:
         dev_t   st_dev

ssh2/session.pyx

@@ -75,7 +75,7 @@ cdef void kbd_callback(const char *name, int name_len,
                        c_ssh2.LIBSSH2_USERAUTH_KBDINT_RESPONSE *responses,
                        void **abstract):
     py_sess = (<Session>c_dereference(abstract))
-    if py_sess._kbd_callback==None:
+    if py_sess._kbd_callback is None:
         return
     cdef bytes b_password = to_bytes(py_sess._kbd_callback())
     cdef char *_password = b_password
@@ -560,8 +560,10 @@ cdef class Session:
         cdef int rc
         cdef bytes b_username = to_bytes(username)
         cdef const char *_username = b_username
+
         def passwd():
             return(password)
+
         self._kbd_callback = passwd
         rc = c_ssh2.libssh2_userauth_keyboard_interactive(
             self._session, _username, &kbd_callback)