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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 _correct_splitlines_in_headers(markers, lines):
 """ Corrects markers by removing splitlines deemed to be inside header blocks. """

    updated_markers = ""
    i = 0
    in_header_block = False
    for m in markers:
        # Only set in_header_block flag when we hit an 's' and line is a header
        if m == 's':
            if not in_header_block:
                if bool(re.search(RE_HEADER, lines[i])):
                    in_header_block = True
            else:
                if QUOT_PATTERN.match(lines[i]):
                    m = 'm'
                else:
                    m = 't'

        # If the line is not a header line, set in_header_block false.
        if not bool(re.search(RE_HEADER, lines[i])):
            in_header_block = False

        # Add the marker to the new updated markers string.
        updated_markers += m
        i += 1

    return updated_markers