'Interpolate all items from a dict.
Args:
input_dict: dict to interpolate
Returns:
original dict with all string values interpolated'

def InterpolateDict(self, input_dict):

    new_args = {}
    for (key, value) in input_dict.items():
        if isinstance(value, basestring):
            new_args[key] = self._GetSingleExpansion(value)
        elif isinstance(value, list):
            new_args[key] = self.InterpolateList(value)
        else:
            new_args[key] = value
    return new_args
