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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 remove_initial_spaces_and_mark_message_lines(lines):
 """ Removes the initial spaces in each line before marking message lines. This ensures headers can be identified if they are indented with spaces. """

    i = 0
    while i < len(lines):
        lines[i] = lines[i].lstrip(' ')
        i += 1
    return mark_message_lines(lines)