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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 toString(value):
 """ Convert a value to a string, if possible. """

        if isinstance(value, basestring):
            return value
        elif type(value) in [np.string_, np.str_]:
            return str(value)
        elif type(value) == np.unicode_:
            return unicode(value)
        else:
            raise TypeError("Could not convert %s to string type" % type(value))