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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 getdoc(object):
 """Get the documentation string for an object. All tabs are expanded to spaces. To clean up docstrings that are indented to line up with blocks of code, any whitespace than can be uniformly removed from the second line onwards is removed."""

    try:
        doc = object.__doc__
    except AttributeError:
        return None
    if not isinstance(doc, (str, unicode)):
        return None
    try:
        lines = string.split(string.expandtabs(doc), '\n')
    except UnicodeError:
        return None
    else:
        margin = None
        for line in lines[1:]:
            content = len(string.lstrip(line))
            if not content: continue
            indent = len(line) - content
            if margin is None: margin = indent
            else: margin = min(margin, indent)
        if margin is not None:
            for i in range(1, len(lines)): lines[i] = lines[i][margin:]
        return string.join(lines, '\n')