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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 extract_keypairs(lines, regexer):
 """Given some lines of text, extract key-value pairs from them"""

    updates = {}
    for line in lines:
        # for consistency we must match the replacer and strip whitespace / newlines
        match = regexer.match(line.strip())
        if not match:
            continue
        k_v = match.groupdict()
        updates[k_v[Constants.KEY_GROUP]] = k_v[Constants.VALUE_GROUP]
    return updates