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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 is_mixed_script(string, allowed_aliases=['COMMON']):
 """Checks if ``string`` contains mixed-scripts content, excluding script blocks aliases in ``allowed_aliases``. E.g. ``B. C`` is not considered mixed-scripts by default: it contains characters from **Latin** and **Common**, but **Common** is excluded by default. False False True True :param string: A unicode string :type string: str :param allowed_aliases: Script blocks aliases not to consider. :type allowed_aliases: list(str) :return: Whether ``string`` is considered mixed-scripts or not. :rtype: bool """

    allowed_aliases = [a.upper() for a in allowed_aliases]
    cats = unique_aliases(string) - set(allowed_aliases)
    return len(cats) > 1