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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 fix_var_name(var_name):
 """Clean up and apply standard formatting to variable names."""

    name = var_name.strip()
    for char in '(). /#,':
        name = name.replace(char, '_')
    name = name.replace('+', 'pos_')
    name = name.replace('-', 'neg_')
    if name.endswith('_'):
        name = name[:-1]
    return name