def _dedentlines(lines, tabsize=8, skip_first_line=False):
    DEBUG = False
    if DEBUG:
        print("dedent: dedent(..., tabsize=%d, skip_first_line=%r)"\
              % (tabsize, skip_first_line))
    indents = []
    margin = None
    for i, line in enumerate(lines):
        if i == 0 and skip_first_line: continue
        indent = 0
        for ch in line:
            if ch == ' ':
                indent += 1
            elif ch == '\t':
                indent += tabsize - (indent % tabsize)
            elif ch in '\r\n':
                continue # skip all-whitespace lines
            else:
                break
        else:
            continue # skip all-whitespace lines
        if DEBUG: print("dedent: indent=%d: %r" % (indent, line))
        if margin is None:
            margin = indent
        else:
            margin = min(margin, indent)
    if DEBUG: print("dedent: margin=%r" % margin)

    if margin is not None and margin > 0:
        for i, line in enumerate(lines):
            if i == 0 and skip_first_line: continue
            removed = 0
            for j, ch in enumerate(line):
                if ch == ' ':
                    removed += 1
                elif ch == '\t':
                    removed += tabsize - (removed % tabsize)
                elif ch in '\r\n':
                    if DEBUG: print("dedent: %r: EOL -> strip up to EOL" % line)
                    lines[i] = lines[i][j:]
                    break
                else:
                    raise ValueError("unexpected non-whitespace char %r in "
                                     "line %r while removing %d-space margin"
                                     % (ch, line, margin))
                if DEBUG:
                    print("dedent: %r: %r -> removed %d/%d"\
                          % (line, ch, removed, margin))
                if removed == margin:
                    lines[i] = lines[i][j+1:]
                    break
                elif removed > margin:
                    lines[i] = ' '*(removed-margin) + lines[i][j+1:]
                    break
            else:
                if removed:
                    lines[i] = lines[i][removed:]
    return lines
handle_request must return a HttpResponse
dataset/ETHPy150Open an0/Letterpress/code/markdown2/test/test_markdown2.py/_dedentlines--crossover with--dataset/ETHPy150Open rapidsms/rapidsms-core-dev/lib/rapidsms/tests/backend/test_http.py/test_handle_bad_request