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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_negative(pattern, flags):
 """Check if negative pattern."""


    if flags & MINUSNEGATE:
        return flags & NEGATE and pattern[0:1] in MINUS_NEGATIVE_SYM
    else:
        return flags & NEGATE and pattern[0:1] in NEGATIVE_SYM