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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 _check_voSet(orb,kwargs,funcName):
 """Function to check whether vo is set, because it's required for funcName"""

    if not orb._voSet and kwargs.get('vo',None) is None:
        warnings.warn("Method %s(.) requires vo to be given at Orbit initialization or at method evaluation; using default vo which is %f km/s" % (funcName,orb._vo),
                      galpyWarning)