Why does it spend so much time on sequence selecting?

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select sequence_name.NEXTVAL
from
dual


call count cpu elapsed disk query current rows
------- ------ -------- ---------- ---------- ---------- ---------- ----------
Parse 78531 12.71 12.72 0 0 0 0
Execute 78531 3.75 3.45 0 0 0 0
Fetch 78531 8.34 7.35 2 78531 314127 78531
------- ------ -------- ---------- ---------- ---------- ---------- ----------
total 235593 24.80 23.52 2 78531 314127 78531

Misses in library cache during parse: 0
Optimizer goal: RULE
Parsing user id: 40 (USER_NAME)

Rows Execution Plan
------- ---------------------------------------------------
0 SELECT STATEMENT GOAL: RULE
0 SEQUENCE OF 'SEQUENCE_NAME'
0 TABLE ACCESS GOAL: ANALYZED (FULL) OF 'DUAL'

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