code: def test_YMD_could_be_day():
      ymd = _ymd("foo bar 124 baz")
  
      ymd.append(2, "M")
      assert ymd.has_month
      assert not ymd.has_year
      assert ymd.could_be_day(4)
      assert not ymd.could_be_day(-6)
      assert not ymd.could_be_day(32)
  
      # Assumes leap year
      assert ymd.could_be_day(29)
  
      ymd.append(1999)
      assert ymd.has_year
      assert not ymd.could_be_day(29)
  
      ymd.append(16, "D")
      assert ymd.has_day
      assert not ymd.could_be_day(1)
  
      ymd = _ymd("foo bar 124 baz")
      ymd.append(1999)
      assert ymd.could_be_day(31)
  
imports: import sys
  import pytest
  from dateutil.parser._parser import _ymd
  from dateutil import tz
label_desc: Use image node_id 1 for calling a global function with example usage: test_YMD_could_be_day() without return types