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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_letter(uni_char):
 """Determine whether the given Unicode character is a Unicode letter"""

    category = Category.get(uni_char)
    return (category == Category.UPPERCASE_LETTER or
            category == Category.LOWERCASE_LETTER or
            category == Category.TITLECASE_LETTER or
            category == Category.MODIFIER_LETTER or
            category == Category.OTHER_LETTER)