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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 convertToFree(stream, length_limit=True):
 """Convert stream from fixed source form to free source form."""

    linestack = []
        
    for line in stream:
        convline = FortranLine(line, length_limit)
        
        if convline.is_regular:
            if convline.isContinuation and linestack: 
                linestack[0].continueLine()
            for l in linestack:
                yield str(l)
            linestack = []
            
        linestack.append(convline)
        
    for l in linestack:
        yield str(l)