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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 get_create_parameter(model, param):
 """Return parameter with given name, creating it if needed. If unique is false and the parameter exists, the value is not changed; if it does not exist, it will be created. If unique is true then upon conflict a number is added to the end of the parameter name. Parameters model : pysb.Model The model to add the parameter to param : Param An assembly parameter object """

    norm_name = _n(param.name)
    parameter = model.parameters.get(norm_name)

    if not param.unique and parameter is not None:
        return parameter

    if param.unique:
        pnum = 1
        while True:
            pname = norm_name + '_%d' % pnum
            if model.parameters.get(pname) is None:
                break
            pnum += 1
    else:
        pname = norm_name

    parameter = Parameter(pname, param.value)
    model.add_component(parameter)
    return parameter