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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 _exprparser( expr, scope, lang=None, conf=None, configurable=None, safe=DEFAULT_SAFE, besteffort=DEFAULT_BESTEFFORT, tostr=False ):
 """In charge of parsing an expression and return a python object."""


    if scope is None:
        scope = {}

    scope.update({
        'configurable': configurable,
        'conf': conf
    })

    expr = REGEX_EXPR_R.sub(
        _refrepl(
            configurable=configurable, conf=conf, safe=safe, scope=scope,
            besteffort=besteffort
        ), expr
    )

    result = resolve(
        expr=expr, name=lang, safe=safe, scope=scope, tostr=tostr,
        besteffort=besteffort
    )

    return result