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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 __safe_name(self, method_name):
 """Restrict method name to a-zA-Z0-9_, first char lowercase."""

    # Endpoints backend restricts what chars are allowed in a method name.
    safe_name = re.sub(r'[^\.a-zA-Z0-9_]', '', method_name)

    # Strip any number of leading underscores.
    safe_name = safe_name.lstrip('_')

    # Ensure the first character is lowercase.
    # Slice from 0:1 rather than indexing [0] in case safe_name is length 0.
    return safe_name[0:1].lower() + safe_name[1:]