code: def chirp_quadratic(t, f0, f1, t1, vertex_zero=True):
      if vertex_zero:
          f = f0 + (f1 - f0) * t**2 / t1**2
      else:
          f = f1 - (f1 - f0) * (t1 - t) ** 2 / t1**2
      return f
  
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_equal, assert_, assert_allclose, assert_array_equal
  from pytest import raises
  import scipy.signal.waveforms
label_desc: Use image node_id 2 for calling a global function with example usage: chirp_quadratic(t, f0, f1, t1, vertex_zero) and returns: f