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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def perspective(fovy, aspect, znear, zfar):
 """Create perspective projection matrix Parameters fovy : float The field of view along the y axis. aspect : float Aspect ratio of the view. znear : float Near coordinate of the field of view. zfar : float Far coordinate of the field of view. Returns ------- M : ndarray Perspective projection matrix (4x4). """

    assert(znear != zfar)
    h = math.tan(fovy / 360.0 * math.pi) * znear
    w = h * aspect
    return frustum(-w, w, -h, h, znear, zfar)