import re


def wrapinto_string(content_in_Lines):
    """
     gets a list of lines read from a file
     returns a single string, where all lines are merged
     with special white-space chars are removed and extra spaces trimmed into 1
    """

    res = " ".join(content_in_Lines)

    # remove certain special characters from the string
    for c in {'\a', '\b', '\f', '\n', '\r', '\t'}:
        res = res.replace(c, ' ')

    r1 = re.compile(' {2,}')      # strips off the extra white-spaces
    res = re.sub(r1, ' ', res)

    return res.strip()