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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_symbol(units) -> str: """Get default symbol type. Parameters units_str : string Units. Returns ------- string LaTeX formatted symbol. """

    if kind(units) == "energy":
        d = {}
        d["nm"] = r"\lambda"
        d["wn"] = r"\bar\nu"
        d["eV"] = r"\hslash\omega"
        d["Hz"] = r"f"
        d["THz"] = r"f"
        d["GHz"] = r"f"
        return d.get(units, "E")
    elif kind(units) == "delay":
        return r"\tau"
    elif kind(units) == "fluence":
        return r"\mathcal{F}"
    elif kind(units) == "pulse_width":
        return r"\sigma"
    elif kind(units) == "temperature":
        return r"T"
    else:
        return kind(units)