def OpenPrice(priceSequence):
    Open=priceSequence[0]
    return (Open)
def ClosePrice(pricesequence):
    #Close=priceSequence[-1]
    Close=priceSequence[-1]
    return(Close)
def HighPrice(priceSequence):
    High=priceSequence[0]
    for price in priceSequence:
        if price>High:
           High=price
    return(High)
def LowPrice(priceSequence):
    low=priceSequence[0]
    for price in priceSequence:
        if price<low:
            low=price
    return(low)

  File "<ipython-input-27-d9026ee7567d>", line 3, in <module>
    PrA.ClosePrice(price)

  File "F:\eclipse-workspace\python_learning\priceAnalysis.py", line 12, in ClosePrice
    Close=priceSequence[-1]

NameError: name 'priceSequence' is not defined

PrA.HighPrice(price)
Out[28]: 22

PrA.LowPrice(price)
Out[29]: 17

PrA.ClosePrice(price)
Traceback (most recent call last):

  File "<ipython-input-30-9dfd270d0cc1>", line 1, in <module>
    PrA.ClosePrice(price)

  File "F:\eclipse-workspace\python_learning\priceAnalysis.py", line 12, in ClosePrice
    Close=priceSequence[-1]

NameError: name 'priceSequence' is not defined

PrA.ClosePrice(price)
Traceback (most recent call last):

  File "<ipython-input-31-9dfd270d0cc1>", line 1, in <module>
    PrA.ClosePrice(price)

  File "F:\eclipse-workspace\python_learning\priceAnalysis.py", line 13, in ClosePrice
    Close=priceSequence[-1]

NameError: name 'priceSequence' is not defined

PrA.ClosePrice(price)