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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 draw_texture(tex):
 """Draw a 2D texture to the current viewport Parameters tex : instance of Texture2D The texture to draw. """

    from .program import Program
    program = Program(vert_draw, frag_draw)
    program['u_texture'] = tex
    program['a_position'] = [[-1., -1.], [-1., 1.], [1., -1.], [1., 1.]]
    program['a_texcoord'] = [[0., 1.], [0., 0.], [1., 1.], [1., 0.]]
    program.draw('triangle_strip')