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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 project_surface(surface, angle=DEFAULT_ANGLE):
 """Returns the height of the surface when projected at the given angle. Args: surface (surface):
 the surface to project angle (float):
 the angle at which to project the surface Returns: surface: A projected surface. """

    z_coef = np.sin(np.radians(angle))
    y_coef = np.cos(np.radians(angle))

    surface_height, surface_width = surface.shape
    slope = np.tile(np.linspace(0., 1., surface_height), [surface_width, 1]).T

    return slope * y_coef + surface * z_coef