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Missing Values in DataFrames
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Missing Values in DataFrames

MediumPython

Problem

Write code to calculate the number of missing values in a specific DataFrame column, and outline your strategy for handling those missing values.

For grading, represent the selected column as a Python list, using None for each missing value. Return the missing-value count, then explain when to remove, impute, or flag missing entries.

Constraints

  • 0 <= len(column) <= 10^5
  • Each entry is either None or a valid non-missing value
  • None is the only representation of a missing value

Function Signature

def count_missing_values(column):
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