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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 _validate_label(self, label):
 """Validates label, raising error if invalid."""


        letter_pattern = compile("^[a-z]{1}$")
        number_pattern = compile("^[0]{1}$|^[1-9]{1,2}$")
        icon_pattern = compile("^[a-zA-Z ]{1,}$")

        if not match(letter_pattern, label)\
            and not match(number_pattern, label)\
                and not match(icon_pattern, label):
                    raise InvalidLabelError(
                        "{} is not a valid label".format(label)
                    )

        return label