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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 _set_label_text(obj, text, tooltip=None, replace_all=False):
 """ Keep text before first colon and replace the rest with new text. If there is no colon in the :param obj: :param text: :param tooltip: :param replace_all: No colon is searched and whole text is replaced :return: """

    dlab = str(obj.text())
    index_of_colon = dlab.find(': ')
    if index_of_colon == -1:
        index_of_colon = 0
    else:
        index_of_colon += 2
    if replace_all:
        index_of_colon = 0
    obj.setText(dlab[:index_of_colon] + '%s' % text)
    if tooltip is not None:
        obj.setToolTip(tooltip)