Remove spaces

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examples/regex/remove_spaces.py

line = "  ab cd  "

res = line.lstrip(" ")
print(f"'{res}'")        # 'ab cd  '

res = line.rstrip(" ")
print(f"'{res}'")        # '  ab cd'

res = line.strip(" ")
print(f"'{res}'")        # 'ab cd'

res = line.replace(" ", "")
print(f"'{res}'")        # 'abcd'