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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 spher2cart(rho, theta, phi):
 """Spherical to Cartesian coordinate conversion."""

    st = np.sin(theta)
    sp = np.sin(phi)
    ct = np.cos(theta)
    cp = np.cos(phi)
    rhost = rho * st
    x = rhost * cp
    y = rhost * sp
    z = rho * ct
    return np.array([x, y, z])