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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 jacobian(expr, symbols):
 """ Derive a symbolic expr w.r.t. each symbol in symbols. This returns a symbolic jacobian vector. :param expr: A sympy Expr. :param symbols: The symbols w.r.t. which to derive. """

    jac = []
    for symbol in symbols:
        # Differentiate to every param
        f = sympy.diff(expr, symbol)
        jac.append(f)
    return jac