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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 count_upper(s):
    """ Given a string s, count the number of uppercase vowels in even indices. count_upper('aBCdEf') returns 1 count_upper('abcdefg') returns 0 count_upper('dBBE') returns 0 """
    count = 0
    for i in range(0,len(s),2):
        if s[i] in "AEIOU":
            count += 1
    return count
