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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 text_to_qcolor(text):
 """ Create a QColor from specified string Avoid warning from Qt when an invalid QColor is instantiated """

    color = QColor()
    if not is_string(text): # testing for QString (PyQt API#1)
        text = str(text)
    if not is_text_string(text):
        return color
    if text.startswith('#') and len(text)==7:
        correct = '#0123456789abcdef'
        for char in text:
            if char.lower() not in correct:
                return color
    elif text not in list(QColor.colorNames()):
        return color
    color.setNamedColor(text)
    return color